From 4e6c06ca87e10431de842ccdd15bd2fd23393922 Mon Sep 17 00:00:00 2001
From: Will Charczuk <will@blendlabs.com>
Date: Fri, 12 Oct 2018 09:23:56 -0700
Subject: [PATCH] removing coverage artifact

---
 .gitignore    |     1 +
 coverage.html | 11486 ------------------------------------------------
 2 files changed, 1 insertion(+), 11486 deletions(-)
 delete mode 100644 coverage.html
diff --git a/.gitignore b/.gitignore
index ab2dcb7..3e4b6e1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,4 @@
 # Other
 .vscode
 .DS_Store
+coverage.html
\ No newline at end of file
diff --git a/coverage.html b/coverage.html
deleted file mode 100644
index 9957897..0000000
--- a/coverage.html
+++ /dev/null
@@ -1,11486 +0,0 @@
-
-<!DOCTYPE html>
-<html>
-	<head>
-		<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
-		<style>
-			body {
-				background: black;
-				color: rgb(80, 80, 80);
-			}
-			body, pre, #legend span {
-				font-family: Menlo, monospace;
-				font-weight: bold;
-			}
-			#topbar {
-				background: black;
-				position: fixed;
-				top: 0; left: 0; right: 0;
-				height: 42px;
-				border-bottom: 1px solid rgb(80, 80, 80);
-			}
-			#content {
-				margin-top: 50px;
-			}
-			#nav, #legend {
-				float: left;
-				margin-left: 10px;
-			}
-			#legend {
-				margin-top: 12px;
-			}
-			#nav {
-				margin-top: 10px;
-			}
-			#legend span {
-				margin: 0 5px;
-			}
-			.cov0 { color: rgb(192, 0, 0) }
-.cov1 { color: rgb(128, 128, 128) }
-.cov2 { color: rgb(116, 140, 131) }
-.cov3 { color: rgb(104, 152, 134) }
-.cov4 { color: rgb(92, 164, 137) }
-.cov5 { color: rgb(80, 176, 140) }
-.cov6 { color: rgb(68, 188, 143) }
-.cov7 { color: rgb(56, 200, 146) }
-.cov8 { color: rgb(44, 212, 149) }
-.cov9 { color: rgb(32, 224, 152) }
-.cov10 { color: rgb(20, 236, 155) }
-
-		</style>
-	</head>
-	<body>
-		<div id="topbar">
-			<div id="nav">
-				<select id="files">
-				
-				<option value="file0">github.com/wcharczuk/go-chart/annotation_series.go (77.8%)</option>
-				
-				<option value="file1">github.com/wcharczuk/go-chart/bar_chart.go (95.8%)</option>
-				
-				<option value="file2">github.com/wcharczuk/go-chart/bollinger_band_series.go (68.8%)</option>
-				
-				<option value="file3">github.com/wcharczuk/go-chart/box.go (82.5%)</option>
-				
-				<option value="file4">github.com/wcharczuk/go-chart/chart.go (71.8%)</option>
-				
-				<option value="file5">github.com/wcharczuk/go-chart/colors.go (100.0%)</option>
-				
-				<option value="file6">github.com/wcharczuk/go-chart/concat_series.go (65.0%)</option>
-				
-				<option value="file7">github.com/wcharczuk/go-chart/continuous_range.go (93.3%)</option>
-				
-				<option value="file8">github.com/wcharczuk/go-chart/continuous_series.go (100.0%)</option>
-				
-				<option value="file9">github.com/wcharczuk/go-chart/draw.go (57.4%)</option>
-				
-				<option value="file10">github.com/wcharczuk/go-chart/drawing/color.go (59.5%)</option>
-				
-				<option value="file11">github.com/wcharczuk/go-chart/drawing/curve.go (42.0%)</option>
-				
-				<option value="file12">github.com/wcharczuk/go-chart/drawing/dasher.go (0.0%)</option>
-				
-				<option value="file13">github.com/wcharczuk/go-chart/drawing/demux_flattener.go (0.0%)</option>
-				
-				<option value="file14">github.com/wcharczuk/go-chart/drawing/flattener.go (0.0%)</option>
-				
-				<option value="file15">github.com/wcharczuk/go-chart/drawing/free_type_path.go (0.0%)</option>
-				
-				<option value="file16">github.com/wcharczuk/go-chart/drawing/line.go (0.0%)</option>
-				
-				<option value="file17">github.com/wcharczuk/go-chart/drawing/matrix.go (0.0%)</option>
-				
-				<option value="file18">github.com/wcharczuk/go-chart/drawing/painter.go (0.0%)</option>
-				
-				<option value="file19">github.com/wcharczuk/go-chart/drawing/path.go (0.0%)</option>
-				
-				<option value="file20">github.com/wcharczuk/go-chart/drawing/raster_graphic_context.go (0.0%)</option>
-				
-				<option value="file21">github.com/wcharczuk/go-chart/drawing/stack_graphic_context.go (0.0%)</option>
-				
-				<option value="file22">github.com/wcharczuk/go-chart/drawing/stroker.go (0.0%)</option>
-				
-				<option value="file23">github.com/wcharczuk/go-chart/drawing/text.go (0.0%)</option>
-				
-				<option value="file24">github.com/wcharczuk/go-chart/drawing/transformer.go (0.0%)</option>
-				
-				<option value="file25">github.com/wcharczuk/go-chart/drawing/util.go (0.0%)</option>
-				
-				<option value="file26">github.com/wcharczuk/go-chart/ema_series.go (58.7%)</option>
-				
-				<option value="file27">github.com/wcharczuk/go-chart/first_value_annotation.go (77.8%)</option>
-				
-				<option value="file28">github.com/wcharczuk/go-chart/font.go (88.9%)</option>
-				
-				<option value="file29">github.com/wcharczuk/go-chart/grid_line.go (34.5%)</option>
-				
-				<option value="file30">github.com/wcharczuk/go-chart/histogram_series.go (35.3%)</option>
-				
-				<option value="file31">github.com/wcharczuk/go-chart/image_writer.go (0.0%)</option>
-				
-				<option value="file32">github.com/wcharczuk/go-chart/jet.go (0.0%)</option>
-				
-				<option value="file33">github.com/wcharczuk/go-chart/last_value_annotation.go (77.8%)</option>
-				
-				<option value="file34">github.com/wcharczuk/go-chart/legend.go (32.5%)</option>
-				
-				<option value="file35">github.com/wcharczuk/go-chart/linear_coefficient_provider.go (0.0%)</option>
-				
-				<option value="file36">github.com/wcharczuk/go-chart/linear_regression_series.go (64.3%)</option>
-				
-				<option value="file37">github.com/wcharczuk/go-chart/linear_series.go (0.0%)</option>
-				
-				<option value="file38">github.com/wcharczuk/go-chart/macd_series.go (49.5%)</option>
-				
-				<option value="file39">github.com/wcharczuk/go-chart/matrix/matrix.go (81.0%)</option>
-				
-				<option value="file40">github.com/wcharczuk/go-chart/matrix/regression.go (90.9%)</option>
-				
-				<option value="file41">github.com/wcharczuk/go-chart/matrix/util.go (58.3%)</option>
-				
-				<option value="file42">github.com/wcharczuk/go-chart/matrix/vector.go (0.0%)</option>
-				
-				<option value="file43">github.com/wcharczuk/go-chart/min_max_series.go (0.0%)</option>
-				
-				<option value="file44">github.com/wcharczuk/go-chart/pie_chart.go (70.6%)</option>
-				
-				<option value="file45">github.com/wcharczuk/go-chart/polynomial_regression_series.go (45.6%)</option>
-				
-				<option value="file46">github.com/wcharczuk/go-chart/raster_renderer.go (74.1%)</option>
-				
-				<option value="file47">github.com/wcharczuk/go-chart/seq/array.go (100.0%)</option>
-				
-				<option value="file48">github.com/wcharczuk/go-chart/seq/buffer.go (69.9%)</option>
-				
-				<option value="file49">github.com/wcharczuk/go-chart/seq/linear.go (94.7%)</option>
-				
-				<option value="file50">github.com/wcharczuk/go-chart/seq/random.go (44.0%)</option>
-				
-				<option value="file51">github.com/wcharczuk/go-chart/seq/seq.go (47.0%)</option>
-				
-				<option value="file52">github.com/wcharczuk/go-chart/seq/time.go (78.9%)</option>
-				
-				<option value="file53">github.com/wcharczuk/go-chart/seq/times.go (0.0%)</option>
-				
-				<option value="file54">github.com/wcharczuk/go-chart/seq/util.go (0.0%)</option>
-				
-				<option value="file55">github.com/wcharczuk/go-chart/sma_series.go (54.8%)</option>
-				
-				<option value="file56">github.com/wcharczuk/go-chart/stacked_bar_chart.go (0.0%)</option>
-				
-				<option value="file57">github.com/wcharczuk/go-chart/style.go (66.1%)</option>
-				
-				<option value="file58">github.com/wcharczuk/go-chart/text.go (87.9%)</option>
-				
-				<option value="file59">github.com/wcharczuk/go-chart/tick.go (78.9%)</option>
-				
-				<option value="file60">github.com/wcharczuk/go-chart/time_series.go (69.6%)</option>
-				
-				<option value="file61">github.com/wcharczuk/go-chart/util/date.go (60.9%)</option>
-				
-				<option value="file62">github.com/wcharczuk/go-chart/util/file_util.go (0.0%)</option>
-				
-				<option value="file63">github.com/wcharczuk/go-chart/util/math.go (50.5%)</option>
-				
-				<option value="file64">github.com/wcharczuk/go-chart/util/time.go (53.7%)</option>
-				
-				<option value="file65">github.com/wcharczuk/go-chart/value.go (100.0%)</option>
-				
-				<option value="file66">github.com/wcharczuk/go-chart/value_formatter.go (46.9%)</option>
-				
-				<option value="file67">github.com/wcharczuk/go-chart/vector_renderer.go (56.6%)</option>
-				
-				<option value="file68">github.com/wcharczuk/go-chart/viridis.go (0.0%)</option>
-				
-				<option value="file69">github.com/wcharczuk/go-chart/xaxis.go (60.4%)</option>
-				
-				<option value="file70">github.com/wcharczuk/go-chart/yaxis.go (63.1%)</option>
-				
-				</select>
-			</div>
-			<div id="legend">
-				<span>not tracked</span>
-			
-				<span class="cov0">not covered</span>
-				<span class="cov8">covered</span>
-			
-			</div>
-		</div>
-		<div id="content">
-		
-		<pre class="file" id="file0" style="display: none">package chart
-
-import (
-        "fmt"
-        "math"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// Interface Assertions.
-var (
-        _ Series = (*AnnotationSeries)(nil)
-)
-
-// AnnotationSeries is a series of labels on the chart.
-type AnnotationSeries struct {
-        Name        string
-        Style       Style
-        YAxis       YAxisType
-        Annotations []Value2
-}
-
-// GetName returns the name of the time series.
-func (as AnnotationSeries) GetName() string <span class="cov0" title="0">{
-        return as.Name
-}</span>
-
-// GetStyle returns the line style.
-func (as AnnotationSeries) GetStyle() Style <span class="cov0" title="0">{
-        return as.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (as AnnotationSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return as.YAxis
-}</span>
-
-func (as AnnotationSeries) annotationStyleDefaults(defaults Style) Style <span class="cov8" title="1">{
-        return Style{
-                FontColor:   DefaultTextColor,
-                Font:        defaults.Font,
-                FillColor:   DefaultAnnotationFillColor,
-                FontSize:    DefaultAnnotationFontSize,
-                StrokeColor: defaults.StrokeColor,
-                StrokeWidth: defaults.StrokeWidth,
-                Padding:     DefaultAnnotationPadding,
-        }
-}</span>
-
-// Measure returns a bounds box of the series.
-func (as AnnotationSeries) Measure(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) Box <span class="cov8" title="1">{
-        box := Box{
-                Top:    math.MaxInt32,
-                Left:   math.MaxInt32,
-                Right:  0,
-                Bottom: 0,
-        }
-        if as.Style.IsZero() || as.Style.Show </span><span class="cov8" title="1">{
-                seriesStyle := as.Style.InheritFrom(as.annotationStyleDefaults(defaults))
-                for _, a := range as.Annotations </span><span class="cov8" title="1">{
-                        style := a.Style.InheritFrom(seriesStyle)
-                        lx := canvasBox.Left + xrange.Translate(a.XValue)
-                        ly := canvasBox.Bottom - yrange.Translate(a.YValue)
-                        ab := Draw.MeasureAnnotation(r, canvasBox, style, lx, ly, a.Label)
-                        box.Top = util.Math.MinInt(box.Top, ab.Top)
-                        box.Left = util.Math.MinInt(box.Left, ab.Left)
-                        box.Right = util.Math.MaxInt(box.Right, ab.Right)
-                        box.Bottom = util.Math.MaxInt(box.Bottom, ab.Bottom)
-                }</span>
-        }
-        <span class="cov8" title="1">return box</span>
-}
-
-// Render draws the series.
-func (as AnnotationSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov8" title="1">{
-        if as.Style.IsZero() || as.Style.Show </span><span class="cov8" title="1">{
-                seriesStyle := as.Style.InheritFrom(as.annotationStyleDefaults(defaults))
-                for _, a := range as.Annotations </span><span class="cov8" title="1">{
-                        style := a.Style.InheritFrom(seriesStyle)
-                        lx := canvasBox.Left + xrange.Translate(a.XValue)
-                        ly := canvasBox.Bottom - yrange.Translate(a.YValue)
-                        Draw.Annotation(r, canvasBox, style, lx, ly, a.Label)
-                }</span>
-        }
-}
-
-// Validate validates the series.
-func (as AnnotationSeries) Validate() error <span class="cov0" title="0">{
-        if len(as.Annotations) == 0 </span><span class="cov0" title="0">{
-                return fmt.Errorf("annotation series requires annotations to be set and not empty")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file1" style="display: none">package chart
-
-import (
-        "errors"
-        "fmt"
-        "io"
-        "math"
-
-        "github.com/golang/freetype/truetype"
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// BarChart is a chart that draws bars on a range.
-type BarChart struct {
-        Title      string
-        TitleStyle Style
-
-        ColorPalette ColorPalette
-
-        Width  int
-        Height int
-        DPI    float64
-
-        BarWidth int
-
-        Background Style
-        Canvas     Style
-
-        XAxis Style
-        YAxis YAxis
-
-        BarSpacing int
-
-        UseBaseValue bool
-        BaseValue    float64
-
-        Font        *truetype.Font
-        defaultFont *truetype.Font
-
-        Bars     []Value
-        Elements []Renderable
-}
-
-// GetDPI returns the dpi for the chart.
-func (bc BarChart) GetDPI() float64 <span class="cov8" title="1">{
-        if bc.DPI == 0 </span><span class="cov8" title="1">{
-                return DefaultDPI
-        }</span>
-        <span class="cov8" title="1">return bc.DPI</span>
-}
-
-// GetFont returns the text font.
-func (bc BarChart) GetFont() *truetype.Font <span class="cov8" title="1">{
-        if bc.Font == nil </span><span class="cov8" title="1">{
-                return bc.defaultFont
-        }</span>
-        <span class="cov8" title="1">return bc.Font</span>
-}
-
-// GetWidth returns the chart width or the default value.
-func (bc BarChart) GetWidth() int <span class="cov8" title="1">{
-        if bc.Width == 0 </span><span class="cov8" title="1">{
-                return DefaultChartWidth
-        }</span>
-        <span class="cov8" title="1">return bc.Width</span>
-}
-
-// GetHeight returns the chart height or the default value.
-func (bc BarChart) GetHeight() int <span class="cov8" title="1">{
-        if bc.Height == 0 </span><span class="cov8" title="1">{
-                return DefaultChartHeight
-        }</span>
-        <span class="cov8" title="1">return bc.Height</span>
-}
-
-// GetBarSpacing returns the spacing between bars.
-func (bc BarChart) GetBarSpacing() int <span class="cov8" title="1">{
-        if bc.BarSpacing == 0 </span><span class="cov8" title="1">{
-                return DefaultBarSpacing
-        }</span>
-        <span class="cov8" title="1">return bc.BarSpacing</span>
-}
-
-// GetBarWidth returns the default bar width.
-func (bc BarChart) GetBarWidth() int <span class="cov8" title="1">{
-        if bc.BarWidth == 0 </span><span class="cov8" title="1">{
-                return DefaultBarWidth
-        }</span>
-        <span class="cov8" title="1">return bc.BarWidth</span>
-}
-
-// Render renders the chart with the given renderer to the given io.Writer.
-func (bc BarChart) Render(rp RendererProvider, w io.Writer) error <span class="cov8" title="1">{
-        if len(bc.Bars) == 0 </span><span class="cov8" title="1">{
-                return errors.New("please provide at least one bar")
-        }</span>
-
-        <span class="cov8" title="1">r, err := rp(bc.GetWidth(), bc.GetHeight())
-        if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-
-        <span class="cov8" title="1">if bc.Font == nil </span><span class="cov8" title="1">{
-                defaultFont, err := GetDefaultFont()
-                if err != nil </span><span class="cov0" title="0">{
-                        return err
-                }</span>
-                <span class="cov8" title="1">bc.defaultFont = defaultFont</span>
-        }
-        <span class="cov8" title="1">r.SetDPI(bc.GetDPI())
-
-        bc.drawBackground(r)
-
-        var canvasBox Box
-        var yt []Tick
-        var yr Range
-        var yf ValueFormatter
-
-        canvasBox = bc.getDefaultCanvasBox()
-        yr = bc.getRanges()
-        if yr.GetMax()-yr.GetMin() == 0 </span><span class="cov8" title="1">{
-                return fmt.Errorf("invalid data range; cannot be zero")
-        }</span>
-        <span class="cov8" title="1">yr = bc.setRangeDomains(canvasBox, yr)
-        yf = bc.getValueFormatters()
-
-        if bc.hasAxes() </span><span class="cov8" title="1">{
-                yt = bc.getAxesTicks(r, yr, yf)
-                canvasBox = bc.getAdjustedCanvasBox(r, canvasBox, yr, yt)
-                yr = bc.setRangeDomains(canvasBox, yr)
-        }</span>
-        <span class="cov8" title="1">bc.drawCanvas(r, canvasBox)
-        bc.drawBars(r, canvasBox, yr)
-        bc.drawXAxis(r, canvasBox)
-        bc.drawYAxis(r, canvasBox, yr, yt)
-
-        bc.drawTitle(r)
-        for _, a := range bc.Elements </span><span class="cov0" title="0">{
-                a(r, canvasBox, bc.styleDefaultsElements())
-        }</span>
-
-        <span class="cov8" title="1">return r.Save(w)</span>
-}
-
-func (bc BarChart) drawCanvas(r Renderer, canvasBox Box) <span class="cov8" title="1">{
-        Draw.Box(r, canvasBox, bc.getCanvasStyle())
-}</span>
-
-func (bc BarChart) getRanges() Range <span class="cov8" title="1">{
-        var yrange Range
-        if bc.YAxis.Range != nil &amp;&amp; !bc.YAxis.Range.IsZero() </span><span class="cov8" title="1">{
-                yrange = bc.YAxis.Range
-        }</span> else<span class="cov8" title="1"> {
-                yrange = &amp;ContinuousRange{}
-        }</span>
-
-        <span class="cov8" title="1">if !yrange.IsZero() </span><span class="cov8" title="1">{
-                return yrange
-        }</span>
-
-        <span class="cov8" title="1">if len(bc.YAxis.Ticks) &gt; 0 </span><span class="cov8" title="1">{
-                tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
-                for _, t := range bc.YAxis.Ticks </span><span class="cov8" title="1">{
-                        tickMin = math.Min(tickMin, t.Value)
-                        tickMax = math.Max(tickMax, t.Value)
-                }</span>
-                <span class="cov8" title="1">yrange.SetMin(tickMin)
-                yrange.SetMax(tickMax)
-                return yrange</span>
-        }
-
-        <span class="cov8" title="1">min, max := math.MaxFloat64, -math.MaxFloat64
-        for _, b := range bc.Bars </span><span class="cov8" title="1">{
-                min = math.Min(b.Value, min)
-                max = math.Max(b.Value, max)
-        }</span>
-
-        <span class="cov8" title="1">yrange.SetMin(min)
-        yrange.SetMax(max)
-
-        return yrange</span>
-}
-
-func (bc BarChart) drawBackground(r Renderer) <span class="cov8" title="1">{
-        Draw.Box(r, Box{
-                Right:  bc.GetWidth(),
-                Bottom: bc.GetHeight(),
-        }, bc.getBackgroundStyle())
-}</span>
-
-func (bc BarChart) drawBars(r Renderer, canvasBox Box, yr Range) <span class="cov8" title="1">{
-        xoffset := canvasBox.Left
-
-        width, spacing, _ := bc.calculateScaledTotalWidth(canvasBox)
-        bs2 := spacing &gt;&gt; 1
-
-        var barBox Box
-        var bxl, bxr, by int
-        for index, bar := range bc.Bars </span><span class="cov8" title="1">{
-                bxl = xoffset + bs2
-                bxr = bxl + width
-
-                by = canvasBox.Bottom - yr.Translate(bar.Value)
-
-                if bc.UseBaseValue </span><span class="cov0" title="0">{
-                        barBox = Box{
-                                Top:    by,
-                                Left:   bxl,
-                                Right:  bxr,
-                                Bottom: canvasBox.Bottom - yr.Translate(bc.BaseValue),
-                        }
-                }</span> else<span class="cov8" title="1"> {
-                        barBox = Box{
-                                Top:    by,
-                                Left:   bxl,
-                                Right:  bxr,
-                                Bottom: canvasBox.Bottom,
-                        }
-                }</span>
-
-                <span class="cov8" title="1">Draw.Box(r, barBox, bar.Style.InheritFrom(bc.styleDefaultsBar(index)))
-
-                xoffset += width + spacing</span>
-        }
-}
-
-func (bc BarChart) drawXAxis(r Renderer, canvasBox Box) <span class="cov8" title="1">{
-        if bc.XAxis.Show </span><span class="cov8" title="1">{
-                axisStyle := bc.XAxis.InheritFrom(bc.styleDefaultsAxes())
-                axisStyle.WriteToRenderer(r)
-
-                width, spacing, _ := bc.calculateScaledTotalWidth(canvasBox)
-
-                r.MoveTo(canvasBox.Left, canvasBox.Bottom)
-                r.LineTo(canvasBox.Right, canvasBox.Bottom)
-                r.Stroke()
-
-                r.MoveTo(canvasBox.Left, canvasBox.Bottom)
-                r.LineTo(canvasBox.Left, canvasBox.Bottom+DefaultVerticalTickHeight)
-                r.Stroke()
-
-                cursor := canvasBox.Left
-                for index, bar := range bc.Bars </span><span class="cov8" title="1">{
-                        barLabelBox := Box{
-                                Top:    canvasBox.Bottom + DefaultXAxisMargin,
-                                Left:   cursor,
-                                Right:  cursor + width + spacing,
-                                Bottom: bc.GetHeight(),
-                        }
-
-                        if len(bar.Label) &gt; 0 </span><span class="cov8" title="1">{
-                                Draw.TextWithin(r, bar.Label, barLabelBox, axisStyle)
-                        }</span>
-
-                        <span class="cov8" title="1">axisStyle.WriteToRenderer(r)
-                        if index &lt; len(bc.Bars)-1 </span><span class="cov8" title="1">{
-                                r.MoveTo(barLabelBox.Right, canvasBox.Bottom)
-                                r.LineTo(barLabelBox.Right, canvasBox.Bottom+DefaultVerticalTickHeight)
-                                r.Stroke()
-                        }</span>
-                        <span class="cov8" title="1">cursor += width + spacing</span>
-                }
-        }
-}
-
-func (bc BarChart) drawYAxis(r Renderer, canvasBox Box, yr Range, ticks []Tick) <span class="cov8" title="1">{
-        if bc.YAxis.Style.Show </span><span class="cov8" title="1">{
-                axisStyle := bc.YAxis.Style.InheritFrom(bc.styleDefaultsAxes())
-                axisStyle.WriteToRenderer(r)
-
-                r.MoveTo(canvasBox.Right, canvasBox.Top)
-                r.LineTo(canvasBox.Right, canvasBox.Bottom)
-                r.Stroke()
-
-                r.MoveTo(canvasBox.Right, canvasBox.Bottom)
-                r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, canvasBox.Bottom)
-                r.Stroke()
-
-                var ty int
-                var tb Box
-                for _, t := range ticks </span><span class="cov8" title="1">{
-                        ty = canvasBox.Bottom - yr.Translate(t.Value)
-
-                        axisStyle.GetStrokeOptions().WriteToRenderer(r)
-                        r.MoveTo(canvasBox.Right, ty)
-                        r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, ty)
-                        r.Stroke()
-
-                        axisStyle.GetTextOptions().WriteToRenderer(r)
-                        tb = r.MeasureText(t.Label)
-                        Draw.Text(r, t.Label, canvasBox.Right+DefaultYAxisMargin+5, ty+(tb.Height()&gt;&gt;1), axisStyle)
-                }</span>
-
-        }
-}
-
-func (bc BarChart) drawTitle(r Renderer) <span class="cov8" title="1">{
-        if len(bc.Title) &gt; 0 &amp;&amp; bc.TitleStyle.Show </span><span class="cov8" title="1">{
-                r.SetFont(bc.TitleStyle.GetFont(bc.GetFont()))
-                r.SetFontColor(bc.TitleStyle.GetFontColor(bc.GetColorPalette().TextColor()))
-                titleFontSize := bc.TitleStyle.GetFontSize(bc.getTitleFontSize())
-                r.SetFontSize(titleFontSize)
-
-                textBox := r.MeasureText(bc.Title)
-
-                textWidth := textBox.Width()
-                textHeight := textBox.Height()
-
-                titleX := (bc.GetWidth() &gt;&gt; 1) - (textWidth &gt;&gt; 1)
-                titleY := bc.TitleStyle.Padding.GetTop(DefaultTitleTop) + textHeight
-
-                r.Text(bc.Title, titleX, titleY)
-        }</span>
-}
-
-func (bc BarChart) getCanvasStyle() Style <span class="cov8" title="1">{
-        return bc.Canvas.InheritFrom(bc.styleDefaultsCanvas())
-}</span>
-
-func (bc BarChart) styleDefaultsCanvas() Style <span class="cov8" title="1">{
-        return Style{
-                FillColor:   bc.GetColorPalette().CanvasColor(),
-                StrokeColor: bc.GetColorPalette().CanvasStrokeColor(),
-                StrokeWidth: DefaultCanvasStrokeWidth,
-        }
-}</span>
-
-func (bc BarChart) hasAxes() bool <span class="cov8" title="1">{
-        return bc.YAxis.Style.Show
-}</span>
-
-func (bc BarChart) setRangeDomains(canvasBox Box, yr Range) Range <span class="cov8" title="1">{
-        yr.SetDomain(canvasBox.Height())
-        return yr
-}</span>
-
-func (bc BarChart) getDefaultCanvasBox() Box <span class="cov8" title="1">{
-        return bc.box()
-}</span>
-
-func (bc BarChart) getValueFormatters() ValueFormatter <span class="cov8" title="1">{
-        if bc.YAxis.ValueFormatter != nil </span><span class="cov8" title="1">{
-                return bc.YAxis.ValueFormatter
-        }</span>
-        <span class="cov8" title="1">return FloatValueFormatter</span>
-}
-
-func (bc BarChart) getAxesTicks(r Renderer, yr Range, yf ValueFormatter) (yticks []Tick) <span class="cov8" title="1">{
-        if bc.YAxis.Style.Show </span><span class="cov8" title="1">{
-                yticks = bc.YAxis.GetTicks(r, yr, bc.styleDefaultsAxes(), yf)
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-func (bc BarChart) calculateEffectiveBarSpacing(canvasBox Box) int <span class="cov8" title="1">{
-        totalWithBaseSpacing := bc.calculateTotalBarWidth(bc.GetBarWidth(), bc.GetBarSpacing())
-        if totalWithBaseSpacing &gt; canvasBox.Width() </span><span class="cov8" title="1">{
-                lessBarWidths := canvasBox.Width() - (len(bc.Bars) * bc.GetBarWidth())
-                if lessBarWidths &gt; 0 </span><span class="cov0" title="0">{
-                        return int(math.Ceil(float64(lessBarWidths) / float64(len(bc.Bars))))
-                }</span>
-                <span class="cov8" title="1">return 0</span>
-        }
-        <span class="cov8" title="1">return bc.GetBarSpacing()</span>
-}
-
-func (bc BarChart) calculateEffectiveBarWidth(canvasBox Box, spacing int) int <span class="cov8" title="1">{
-        totalWithBaseWidth := bc.calculateTotalBarWidth(bc.GetBarWidth(), spacing)
-        if totalWithBaseWidth &gt; canvasBox.Width() </span><span class="cov8" title="1">{
-                totalLessBarSpacings := canvasBox.Width() - (len(bc.Bars) * spacing)
-                if totalLessBarSpacings &gt; 0 </span><span class="cov8" title="1">{
-                        return int(math.Ceil(float64(totalLessBarSpacings) / float64(len(bc.Bars))))
-                }</span>
-                <span class="cov0" title="0">return 0</span>
-        }
-        <span class="cov8" title="1">return bc.GetBarWidth()</span>
-}
-
-func (bc BarChart) calculateTotalBarWidth(barWidth, spacing int) int <span class="cov8" title="1">{
-        return len(bc.Bars) * (barWidth + spacing)
-}</span>
-
-func (bc BarChart) calculateScaledTotalWidth(canvasBox Box) (width, spacing, total int) <span class="cov8" title="1">{
-        spacing = bc.calculateEffectiveBarSpacing(canvasBox)
-        width = bc.calculateEffectiveBarWidth(canvasBox, spacing)
-        total = bc.calculateTotalBarWidth(width, spacing)
-        return
-}</span>
-
-func (bc BarChart) getAdjustedCanvasBox(r Renderer, canvasBox Box, yrange Range, yticks []Tick) Box <span class="cov8" title="1">{
-        axesOuterBox := canvasBox.Clone()
-
-        _, _, totalWidth := bc.calculateScaledTotalWidth(canvasBox)
-
-        if bc.XAxis.Show </span><span class="cov8" title="1">{
-                xaxisHeight := DefaultVerticalTickHeight
-
-                axisStyle := bc.XAxis.InheritFrom(bc.styleDefaultsAxes())
-                axisStyle.WriteToRenderer(r)
-
-                cursor := canvasBox.Left
-                for _, bar := range bc.Bars </span><span class="cov8" title="1">{
-                        if len(bar.Label) &gt; 0 </span><span class="cov8" title="1">{
-                                barLabelBox := Box{
-                                        Top:    canvasBox.Bottom + DefaultXAxisMargin,
-                                        Left:   cursor,
-                                        Right:  cursor + bc.GetBarWidth() + bc.GetBarSpacing(),
-                                        Bottom: bc.GetHeight(),
-                                }
-                                lines := Text.WrapFit(r, bar.Label, barLabelBox.Width(), axisStyle)
-                                linesBox := Text.MeasureLines(r, lines, axisStyle)
-
-                                xaxisHeight = util.Math.MinInt(linesBox.Height()+(2*DefaultXAxisMargin), xaxisHeight)
-                        }</span>
-                }
-
-                <span class="cov8" title="1">xbox := Box{
-                        Top:    canvasBox.Top,
-                        Left:   canvasBox.Left,
-                        Right:  canvasBox.Left + totalWidth,
-                        Bottom: bc.GetHeight() - xaxisHeight,
-                }
-
-                axesOuterBox = axesOuterBox.Grow(xbox)</span>
-        }
-
-        <span class="cov8" title="1">if bc.YAxis.Style.Show </span><span class="cov8" title="1">{
-                axesBounds := bc.YAxis.Measure(r, canvasBox, yrange, bc.styleDefaultsAxes(), yticks)
-                axesOuterBox = axesOuterBox.Grow(axesBounds)
-        }</span>
-
-        <span class="cov8" title="1">return canvasBox.OuterConstrain(bc.box(), axesOuterBox)</span>
-}
-
-// box returns the chart bounds as a box.
-func (bc BarChart) box() Box <span class="cov8" title="1">{
-        dpr := bc.Background.Padding.GetRight(10)
-        dpb := bc.Background.Padding.GetBottom(50)
-
-        return Box{
-                Top:    bc.Background.Padding.GetTop(20),
-                Left:   bc.Background.Padding.GetLeft(20),
-                Right:  bc.GetWidth() - dpr,
-                Bottom: bc.GetHeight() - dpb,
-        }
-}</span>
-
-func (bc BarChart) getBackgroundStyle() Style <span class="cov8" title="1">{
-        return bc.Background.InheritFrom(bc.styleDefaultsBackground())
-}</span>
-
-func (bc BarChart) styleDefaultsBackground() Style <span class="cov8" title="1">{
-        return Style{
-                FillColor:   bc.GetColorPalette().BackgroundColor(),
-                StrokeColor: bc.GetColorPalette().BackgroundStrokeColor(),
-                StrokeWidth: DefaultStrokeWidth,
-        }
-}</span>
-
-func (bc BarChart) styleDefaultsBar(index int) Style <span class="cov8" title="1">{
-        return Style{
-                StrokeColor: bc.GetColorPalette().GetSeriesColor(index),
-                StrokeWidth: 3.0,
-                FillColor:   bc.GetColorPalette().GetSeriesColor(index),
-        }
-}</span>
-
-func (bc BarChart) styleDefaultsTitle() Style <span class="cov0" title="0">{
-        return bc.TitleStyle.InheritFrom(Style{
-                FontColor:           bc.GetColorPalette().TextColor(),
-                Font:                bc.GetFont(),
-                FontSize:            bc.getTitleFontSize(),
-                TextHorizontalAlign: TextHorizontalAlignCenter,
-                TextVerticalAlign:   TextVerticalAlignTop,
-                TextWrap:            TextWrapWord,
-        })
-}</span>
-
-func (bc BarChart) getTitleFontSize() float64 <span class="cov8" title="1">{
-        effectiveDimension := util.Math.MinInt(bc.GetWidth(), bc.GetHeight())
-        if effectiveDimension &gt;= 2048 </span><span class="cov8" title="1">{
-                return 48
-        }</span> else<span class="cov8" title="1"> if effectiveDimension &gt;= 1024 </span><span class="cov8" title="1">{
-                return 24
-        }</span> else<span class="cov8" title="1"> if effectiveDimension &gt;= 512 </span><span class="cov8" title="1">{
-                return 18
-        }</span> else<span class="cov8" title="1"> if effectiveDimension &gt;= 256 </span><span class="cov8" title="1">{
-                return 12
-        }</span>
-        <span class="cov8" title="1">return 10</span>
-}
-
-func (bc BarChart) styleDefaultsAxes() Style <span class="cov8" title="1">{
-        return Style{
-                StrokeColor:         bc.GetColorPalette().AxisStrokeColor(),
-                Font:                bc.GetFont(),
-                FontSize:            DefaultAxisFontSize,
-                FontColor:           bc.GetColorPalette().TextColor(),
-                TextHorizontalAlign: TextHorizontalAlignCenter,
-                TextVerticalAlign:   TextVerticalAlignTop,
-                TextWrap:            TextWrapWord,
-        }
-}</span>
-
-func (bc BarChart) styleDefaultsElements() Style <span class="cov0" title="0">{
-        return Style{
-                Font: bc.GetFont(),
-        }
-}</span>
-
-// GetColorPalette returns the color palette for the chart.
-func (bc BarChart) GetColorPalette() ColorPalette <span class="cov8" title="1">{
-        if bc.ColorPalette != nil </span><span class="cov0" title="0">{
-                return bc.ColorPalette
-        }</span>
-        <span class="cov8" title="1">return AlternateColorPalette</span>
-}
-</pre>
-		
-		<pre class="file" id="file2" style="display: none">package chart
-
-import (
-        "fmt"
-
-        "github.com/wcharczuk/go-chart/seq"
-)
-
-// Interface Assertions.
-var (
-        _ Series = (*BollingerBandsSeries)(nil)
-)
-
-// BollingerBandsSeries draws bollinger bands for an inner series.
-// Bollinger bands are defined by two lines, one at SMA+k*stddev, one at SMA-k*stdev.
-type BollingerBandsSeries struct {
-        Name  string
-        Style Style
-        YAxis YAxisType
-
-        Period      int
-        K           float64
-        InnerSeries ValuesProvider
-
-        valueBuffer *seq.Buffer
-}
-
-// GetName returns the name of the time series.
-func (bbs BollingerBandsSeries) GetName() string <span class="cov0" title="0">{
-        return bbs.Name
-}</span>
-
-// GetStyle returns the line style.
-func (bbs BollingerBandsSeries) GetStyle() Style <span class="cov0" title="0">{
-        return bbs.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (bbs BollingerBandsSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return bbs.YAxis
-}</span>
-
-// GetPeriod returns the window size.
-func (bbs BollingerBandsSeries) GetPeriod() int <span class="cov8" title="1">{
-        if bbs.Period == 0 </span><span class="cov8" title="1">{
-                return DefaultSimpleMovingAveragePeriod
-        }</span>
-        <span class="cov0" title="0">return bbs.Period</span>
-}
-
-// GetK returns the K value, or the number of standard deviations above and below
-// to band the simple moving average with.
-// Typical K value is 2.0.
-func (bbs BollingerBandsSeries) GetK(defaults ...float64) float64 <span class="cov8" title="1">{
-        if bbs.K == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov0" title="0">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return 2.0</span>
-        }
-        <span class="cov0" title="0">return bbs.K</span>
-}
-
-// Len returns the number of elements in the series.
-func (bbs BollingerBandsSeries) Len() int <span class="cov0" title="0">{
-        return bbs.InnerSeries.Len()
-}</span>
-
-// GetBoundedValues gets the bounded value for the series.
-func (bbs *BollingerBandsSeries) GetBoundedValues(index int) (x, y1, y2 float64) <span class="cov8" title="1">{
-        if bbs.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">if bbs.valueBuffer == nil || index == 0 </span><span class="cov8" title="1">{
-                bbs.valueBuffer = seq.NewBufferWithCapacity(bbs.GetPeriod())
-        }</span>
-        <span class="cov8" title="1">if bbs.valueBuffer.Len() &gt;= bbs.GetPeriod() </span><span class="cov8" title="1">{
-                bbs.valueBuffer.Dequeue()
-        }</span>
-        <span class="cov8" title="1">px, py := bbs.InnerSeries.GetValues(index)
-        bbs.valueBuffer.Enqueue(py)
-        x = px
-
-        ay := seq.New(bbs.valueBuffer).Average()
-        std := seq.New(bbs.valueBuffer).StdDev()
-
-        y1 = ay + (bbs.GetK() * std)
-        y2 = ay - (bbs.GetK() * std)
-        return</span>
-}
-
-// GetBoundedLastValues returns the last bounded value for the series.
-func (bbs *BollingerBandsSeries) GetBoundedLastValues() (x, y1, y2 float64) <span class="cov8" title="1">{
-        if bbs.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">period := bbs.GetPeriod()
-        seriesLength := bbs.InnerSeries.Len()
-        startAt := seriesLength - period
-        if startAt &lt; 0 </span><span class="cov0" title="0">{
-                startAt = 0
-        }</span>
-
-        <span class="cov8" title="1">vb := seq.NewBufferWithCapacity(period)
-        for index := startAt; index &lt; seriesLength; index++ </span><span class="cov8" title="1">{
-                xn, yn := bbs.InnerSeries.GetValues(index)
-                vb.Enqueue(yn)
-                x = xn
-        }</span>
-
-        <span class="cov8" title="1">ay := seq.Seq{Provider: vb}.Average()
-        std := seq.Seq{Provider: vb}.StdDev()
-
-        y1 = ay + (bbs.GetK() * std)
-        y2 = ay - (bbs.GetK() * std)
-
-        return</span>
-}
-
-// Render renders the series.
-func (bbs *BollingerBandsSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        s := bbs.Style.InheritFrom(defaults.InheritFrom(Style{
-                StrokeWidth: 1.0,
-                StrokeColor: DefaultAxisColor.WithAlpha(64),
-                FillColor:   DefaultAxisColor.WithAlpha(32),
-        }))
-
-        Draw.BoundedSeries(r, canvasBox, xrange, yrange, s, bbs, bbs.GetPeriod())
-}</span>
-
-// Validate validates the series.
-func (bbs BollingerBandsSeries) Validate() error <span class="cov0" title="0">{
-        if bbs.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("bollinger bands series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file3" style="display: none">package chart
-
-import (
-        "fmt"
-        "math"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-var (
-        // BoxZero is a preset box that represents an intentional zero value.
-        BoxZero = Box{IsSet: true}
-)
-
-// NewBox returns a new (set) box.
-func NewBox(top, left, right, bottom int) Box <span class="cov8" title="1">{
-        return Box{
-                IsSet:  true,
-                Top:    top,
-                Left:   left,
-                Right:  right,
-                Bottom: bottom,
-        }
-}</span>
-
-// Box represents the main 4 dimensions of a box.
-type Box struct {
-        Top    int
-        Left   int
-        Right  int
-        Bottom int
-        IsSet  bool
-}
-
-// IsZero returns if the box is set or not.
-func (b Box) IsZero() bool <span class="cov8" title="1">{
-        if b.IsSet </span><span class="cov8" title="1">{
-                return false
-        }</span>
-        <span class="cov8" title="1">return b.Top == 0 &amp;&amp; b.Left == 0 &amp;&amp; b.Right == 0 &amp;&amp; b.Bottom == 0</span>
-}
-
-// String returns a string representation of the box.
-func (b Box) String() string <span class="cov8" title="1">{
-        return fmt.Sprintf("box(%d,%d,%d,%d)", b.Top, b.Left, b.Right, b.Bottom)
-}</span>
-
-// GetTop returns a coalesced value with a default.
-func (b Box) GetTop(defaults ...int) int <span class="cov8" title="1">{
-        if !b.IsSet &amp;&amp; b.Top == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return 0</span>
-        }
-        <span class="cov8" title="1">return b.Top</span>
-}
-
-// GetLeft returns a coalesced value with a default.
-func (b Box) GetLeft(defaults ...int) int <span class="cov8" title="1">{
-        if !b.IsSet &amp;&amp; b.Left == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return 0</span>
-        }
-        <span class="cov8" title="1">return b.Left</span>
-}
-
-// GetRight returns a coalesced value with a default.
-func (b Box) GetRight(defaults ...int) int <span class="cov8" title="1">{
-        if !b.IsSet &amp;&amp; b.Right == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return 0</span>
-        }
-        <span class="cov8" title="1">return b.Right</span>
-}
-
-// GetBottom returns a coalesced value with a default.
-func (b Box) GetBottom(defaults ...int) int <span class="cov8" title="1">{
-        if !b.IsSet &amp;&amp; b.Bottom == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return 0</span>
-        }
-        <span class="cov8" title="1">return b.Bottom</span>
-}
-
-// Width returns the width
-func (b Box) Width() int <span class="cov8" title="1">{
-        return util.Math.AbsInt(b.Right - b.Left)
-}</span>
-
-// Height returns the height
-func (b Box) Height() int <span class="cov8" title="1">{
-        return util.Math.AbsInt(b.Bottom - b.Top)
-}</span>
-
-// Center returns the center of the box
-func (b Box) Center() (x, y int) <span class="cov8" title="1">{
-        w2, h2 := b.Width()&gt;&gt;1, b.Height()&gt;&gt;1
-        return b.Left + w2, b.Top + h2
-}</span>
-
-// Aspect returns the aspect ratio of the box.
-func (b Box) Aspect() float64 <span class="cov8" title="1">{
-        return float64(b.Width()) / float64(b.Height())
-}</span>
-
-// Clone returns a new copy of the box.
-func (b Box) Clone() Box <span class="cov8" title="1">{
-        return Box{
-                IsSet:  b.IsSet,
-                Top:    b.Top,
-                Left:   b.Left,
-                Right:  b.Right,
-                Bottom: b.Bottom,
-        }
-}</span>
-
-// IsBiggerThan returns if a box is bigger than another box.
-func (b Box) IsBiggerThan(other Box) bool <span class="cov8" title="1">{
-        return b.Top &lt; other.Top ||
-                b.Bottom &gt; other.Bottom ||
-                b.Left &lt; other.Left ||
-                b.Right &gt; other.Right
-}</span>
-
-// IsSmallerThan returns if a box is smaller than another box.
-func (b Box) IsSmallerThan(other Box) bool <span class="cov8" title="1">{
-        return b.Top &gt; other.Top &amp;&amp;
-                b.Bottom &lt; other.Bottom &amp;&amp;
-                b.Left &gt; other.Left &amp;&amp;
-                b.Right &lt; other.Right
-}</span>
-
-// Equals returns if the box equals another box.
-func (b Box) Equals(other Box) bool <span class="cov8" title="1">{
-        return b.Top == other.Top &amp;&amp;
-                b.Left == other.Left &amp;&amp;
-                b.Right == other.Right &amp;&amp;
-                b.Bottom == other.Bottom
-}</span>
-
-// Grow grows a box based on another box.
-func (b Box) Grow(other Box) Box <span class="cov8" title="1">{
-        return Box{
-                Top:    util.Math.MinInt(b.Top, other.Top),
-                Left:   util.Math.MinInt(b.Left, other.Left),
-                Right:  util.Math.MaxInt(b.Right, other.Right),
-                Bottom: util.Math.MaxInt(b.Bottom, other.Bottom),
-        }
-}</span>
-
-// Shift pushes a box by x,y.
-func (b Box) Shift(x, y int) Box <span class="cov8" title="1">{
-        return Box{
-                Top:    b.Top + y,
-                Left:   b.Left + x,
-                Right:  b.Right + x,
-                Bottom: b.Bottom + y,
-        }
-}</span>
-
-// Corners returns the box as a set of corners.
-func (b Box) Corners() BoxCorners <span class="cov0" title="0">{
-        return BoxCorners{
-                TopLeft:     Point{b.Left, b.Top},
-                TopRight:    Point{b.Right, b.Top},
-                BottomRight: Point{b.Right, b.Bottom},
-                BottomLeft:  Point{b.Left, b.Bottom},
-        }
-}</span>
-
-// Fit is functionally the inverse of grow.
-// Fit maintains the original aspect ratio of the `other` box,
-// but constrains it to the bounds of the target box.
-func (b Box) Fit(other Box) Box <span class="cov8" title="1">{
-        ba := b.Aspect()
-        oa := other.Aspect()
-
-        if oa == ba </span><span class="cov8" title="1">{
-                return b.Clone()
-        }</span>
-
-        <span class="cov8" title="1">bw, bh := float64(b.Width()), float64(b.Height())
-        bw2 := int(bw) &gt;&gt; 1
-        bh2 := int(bh) &gt;&gt; 1
-        if oa &gt; ba </span><span class="cov8" title="1">{ // ex. 16:9 vs. 4:3
-                var noh2 int
-                if oa &gt; 1.0 </span><span class="cov8" title="1">{
-                        noh2 = int(bw/oa) &gt;&gt; 1
-                }</span> else<span class="cov0" title="0"> {
-                        noh2 = int(bh*oa) &gt;&gt; 1
-                }</span>
-                <span class="cov8" title="1">return Box{
-                        Top:    (b.Top + bh2) - noh2,
-                        Left:   b.Left,
-                        Right:  b.Right,
-                        Bottom: (b.Top + bh2) + noh2,
-                }</span>
-        }
-        <span class="cov8" title="1">var now2 int
-        if oa &gt; 1.0 </span><span class="cov0" title="0">{
-                now2 = int(bh/oa) &gt;&gt; 1
-        }</span> else<span class="cov8" title="1"> {
-                now2 = int(bw*oa) &gt;&gt; 1
-        }</span>
-        <span class="cov8" title="1">return Box{
-                Top:    b.Top,
-                Left:   (b.Left + bw2) - now2,
-                Right:  (b.Left + bw2) + now2,
-                Bottom: b.Bottom,
-        }</span>
-}
-
-// Constrain is similar to `Fit` except that it will work
-// more literally like the opposite of grow.
-func (b Box) Constrain(other Box) Box <span class="cov8" title="1">{
-        newBox := b.Clone()
-
-        newBox.Top = util.Math.MaxInt(newBox.Top, other.Top)
-        newBox.Left = util.Math.MaxInt(newBox.Left, other.Left)
-        newBox.Right = util.Math.MinInt(newBox.Right, other.Right)
-        newBox.Bottom = util.Math.MinInt(newBox.Bottom, other.Bottom)
-
-        return newBox
-}</span>
-
-// OuterConstrain is similar to `Constraint` with the difference
-// that it applies corrections
-func (b Box) OuterConstrain(bounds, other Box) Box <span class="cov8" title="1">{
-        newBox := b.Clone()
-        if other.Top &lt; bounds.Top </span><span class="cov8" title="1">{
-                delta := bounds.Top - other.Top
-                newBox.Top = b.Top + delta
-        }</span>
-
-        <span class="cov8" title="1">if other.Left &lt; bounds.Left </span><span class="cov8" title="1">{
-                delta := bounds.Left - other.Left
-                newBox.Left = b.Left + delta
-        }</span>
-
-        <span class="cov8" title="1">if other.Right &gt; bounds.Right </span><span class="cov8" title="1">{
-                delta := other.Right - bounds.Right
-                newBox.Right = b.Right - delta
-        }</span>
-
-        <span class="cov8" title="1">if other.Bottom &gt; bounds.Bottom </span><span class="cov8" title="1">{
-                delta := other.Bottom - bounds.Bottom
-                newBox.Bottom = b.Bottom - delta
-        }</span>
-        <span class="cov8" title="1">return newBox</span>
-}
-
-// BoxCorners is a box with independent corners.
-type BoxCorners struct {
-        TopLeft, TopRight, BottomRight, BottomLeft Point
-}
-
-// Box return the BoxCorners as a regular box.
-func (bc BoxCorners) Box() Box <span class="cov0" title="0">{
-        return Box{
-                Top:    util.Math.MinInt(bc.TopLeft.Y, bc.TopRight.Y),
-                Left:   util.Math.MinInt(bc.TopLeft.X, bc.BottomLeft.X),
-                Right:  util.Math.MaxInt(bc.TopRight.X, bc.BottomRight.X),
-                Bottom: util.Math.MaxInt(bc.BottomLeft.Y, bc.BottomRight.Y),
-        }
-}</span>
-
-// Width returns the width
-func (bc BoxCorners) Width() int <span class="cov0" title="0">{
-        minLeft := util.Math.MinInt(bc.TopLeft.X, bc.BottomLeft.X)
-        maxRight := util.Math.MaxInt(bc.TopRight.X, bc.BottomRight.X)
-        return maxRight - minLeft
-}</span>
-
-// Height returns the height
-func (bc BoxCorners) Height() int <span class="cov0" title="0">{
-        minTop := util.Math.MinInt(bc.TopLeft.Y, bc.TopRight.Y)
-        maxBottom := util.Math.MaxInt(bc.BottomLeft.Y, bc.BottomRight.Y)
-        return maxBottom - minTop
-}</span>
-
-// Center returns the center of the box
-func (bc BoxCorners) Center() (x, y int) <span class="cov8" title="1">{
-
-        left := util.Math.MeanInt(bc.TopLeft.X, bc.BottomLeft.X)
-        right := util.Math.MeanInt(bc.TopRight.X, bc.BottomRight.X)
-        x = ((right - left) &gt;&gt; 1) + left
-
-        top := util.Math.MeanInt(bc.TopLeft.Y, bc.TopRight.Y)
-        bottom := util.Math.MeanInt(bc.BottomLeft.Y, bc.BottomRight.Y)
-        y = ((bottom - top) &gt;&gt; 1) + top
-
-        return
-}</span>
-
-// Rotate rotates the box.
-func (bc BoxCorners) Rotate(thetaDegrees float64) BoxCorners <span class="cov8" title="1">{
-        cx, cy := bc.Center()
-
-        thetaRadians := util.Math.DegreesToRadians(thetaDegrees)
-
-        tlx, tly := util.Math.RotateCoordinate(cx, cy, bc.TopLeft.X, bc.TopLeft.Y, thetaRadians)
-        trx, try := util.Math.RotateCoordinate(cx, cy, bc.TopRight.X, bc.TopRight.Y, thetaRadians)
-        brx, bry := util.Math.RotateCoordinate(cx, cy, bc.BottomRight.X, bc.BottomRight.Y, thetaRadians)
-        blx, bly := util.Math.RotateCoordinate(cx, cy, bc.BottomLeft.X, bc.BottomLeft.Y, thetaRadians)
-
-        return BoxCorners{
-                TopLeft:     Point{tlx, tly},
-                TopRight:    Point{trx, try},
-                BottomRight: Point{brx, bry},
-                BottomLeft:  Point{blx, bly},
-        }
-}</span>
-
-// Equals returns if the box equals another box.
-func (bc BoxCorners) Equals(other BoxCorners) bool <span class="cov0" title="0">{
-        return bc.TopLeft.Equals(other.TopLeft) &amp;&amp;
-                bc.TopRight.Equals(other.TopRight) &amp;&amp;
-                bc.BottomRight.Equals(other.BottomRight) &amp;&amp;
-                bc.BottomLeft.Equals(other.BottomLeft)
-}</span>
-
-func (bc BoxCorners) String() string <span class="cov8" title="1">{
-        return fmt.Sprintf("BoxC{%s,%s,%s,%s}", bc.TopLeft.String(), bc.TopRight.String(), bc.BottomRight.String(), bc.BottomLeft.String())
-}</span>
-
-// Point is an X,Y pair
-type Point struct {
-        X, Y int
-}
-
-// DistanceTo calculates the distance to another point.
-func (p Point) DistanceTo(other Point) float64 <span class="cov0" title="0">{
-        dx := math.Pow(float64(p.X-other.X), 2)
-        dy := math.Pow(float64(p.Y-other.Y), 2)
-        return math.Pow(dx+dy, 0.5)
-}</span>
-
-// Equals returns if a point equals another point.
-func (p Point) Equals(other Point) bool <span class="cov8" title="1">{
-        return p.X == other.X &amp;&amp; p.Y == other.Y
-}</span>
-
-// String returns a string representation of the point.
-func (p Point) String() string <span class="cov8" title="1">{
-        return fmt.Sprintf("P{%d,%d}", p.X, p.Y)
-}</span>
-</pre>
-		
-		<pre class="file" id="file4" style="display: none">package chart
-
-import (
-        "errors"
-        "fmt"
-        "io"
-        "math"
-
-        "github.com/golang/freetype/truetype"
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// Chart is what we're drawing.
-type Chart struct {
-        Title      string
-        TitleStyle Style
-
-        ColorPalette ColorPalette
-
-        Width  int
-        Height int
-        DPI    float64
-
-        Background Style
-        Canvas     Style
-
-        XAxis          XAxis
-        YAxis          YAxis
-        YAxisSecondary YAxis
-
-        Font        *truetype.Font
-        defaultFont *truetype.Font
-
-        Series   []Series
-        Elements []Renderable
-}
-
-// GetDPI returns the dpi for the chart.
-func (c Chart) GetDPI(defaults ...float64) float64 <span class="cov8" title="1">{
-        if c.DPI == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return DefaultDPI</span>
-        }
-        <span class="cov8" title="1">return c.DPI</span>
-}
-
-// GetFont returns the text font.
-func (c Chart) GetFont() *truetype.Font <span class="cov8" title="1">{
-        if c.Font == nil </span><span class="cov8" title="1">{
-                return c.defaultFont
-        }</span>
-        <span class="cov8" title="1">return c.Font</span>
-}
-
-// GetWidth returns the chart width or the default value.
-func (c Chart) GetWidth() int <span class="cov8" title="1">{
-        if c.Width == 0 </span><span class="cov8" title="1">{
-                return DefaultChartWidth
-        }</span>
-        <span class="cov8" title="1">return c.Width</span>
-}
-
-// GetHeight returns the chart height or the default value.
-func (c Chart) GetHeight() int <span class="cov8" title="1">{
-        if c.Height == 0 </span><span class="cov8" title="1">{
-                return DefaultChartHeight
-        }</span>
-        <span class="cov8" title="1">return c.Height</span>
-}
-
-// Render renders the chart with the given renderer to the given io.Writer.
-func (c Chart) Render(rp RendererProvider, w io.Writer) error <span class="cov8" title="1">{
-        if len(c.Series) == 0 </span><span class="cov0" title="0">{
-                return errors.New("please provide at least one series")
-        }</span>
-        <span class="cov8" title="1">if visibleSeriesErr := c.checkHasVisibleSeries(); visibleSeriesErr != nil </span><span class="cov0" title="0">{
-                return visibleSeriesErr
-        }</span>
-
-        <span class="cov8" title="1">c.YAxisSecondary.AxisType = YAxisSecondary
-
-        r, err := rp(c.GetWidth(), c.GetHeight())
-        if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-
-        <span class="cov8" title="1">if c.Font == nil </span><span class="cov8" title="1">{
-                defaultFont, err := GetDefaultFont()
-                if err != nil </span><span class="cov0" title="0">{
-                        return err
-                }</span>
-                <span class="cov8" title="1">c.defaultFont = defaultFont</span>
-        }
-        <span class="cov8" title="1">r.SetDPI(c.GetDPI(DefaultDPI))
-
-        c.drawBackground(r)
-
-        var xt, yt, yta []Tick
-        xr, yr, yra := c.getRanges()
-        canvasBox := c.getDefaultCanvasBox()
-        xf, yf, yfa := c.getValueFormatters()
-
-        xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
-
-        err = c.checkRanges(xr, yr, yra)
-        if err != nil </span><span class="cov8" title="1">{
-                r.Save(w)
-                return err
-        }</span>
-
-        <span class="cov8" title="1">if c.hasAxes() </span><span class="cov8" title="1">{
-                xt, yt, yta = c.getAxesTicks(r, xr, yr, yra, xf, yf, yfa)
-                canvasBox = c.getAxesAdjustedCanvasBox(r, canvasBox, xr, yr, yra, xt, yt, yta)
-                xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
-
-                // do a second pass in case things haven't settled yet.
-                xt, yt, yta = c.getAxesTicks(r, xr, yr, yra, xf, yf, yfa)
-                canvasBox = c.getAxesAdjustedCanvasBox(r, canvasBox, xr, yr, yra, xt, yt, yta)
-                xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
-        }</span>
-
-        <span class="cov8" title="1">if c.hasAnnotationSeries() </span><span class="cov0" title="0">{
-                canvasBox = c.getAnnotationAdjustedCanvasBox(r, canvasBox, xr, yr, yra, xf, yf, yfa)
-                xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
-                xt, yt, yta = c.getAxesTicks(r, xr, yr, yra, xf, yf, yfa)
-        }</span>
-
-        <span class="cov8" title="1">c.drawCanvas(r, canvasBox)
-        c.drawAxes(r, canvasBox, xr, yr, yra, xt, yt, yta)
-        for index, series := range c.Series </span><span class="cov8" title="1">{
-                c.drawSeries(r, canvasBox, xr, yr, yra, series, index)
-        }</span>
-
-        <span class="cov8" title="1">c.drawTitle(r)
-
-        for _, a := range c.Elements </span><span class="cov8" title="1">{
-                a(r, canvasBox, c.styleDefaultsElements())
-        }</span>
-
-        <span class="cov8" title="1">return r.Save(w)</span>
-}
-
-func (c Chart) checkHasVisibleSeries() error <span class="cov8" title="1">{
-        hasVisibleSeries := false
-        var style Style
-        for _, s := range c.Series </span><span class="cov8" title="1">{
-                style = s.GetStyle()
-                hasVisibleSeries = hasVisibleSeries || (style.IsZero() || style.Show)
-        }</span>
-        <span class="cov8" title="1">if !hasVisibleSeries </span><span class="cov0" title="0">{
-                return fmt.Errorf("must have (1) visible series; make sure if you set a style, you set .Show = true")
-        }</span>
-        <span class="cov8" title="1">return nil</span>
-}
-
-func (c Chart) validateSeries() error <span class="cov8" title="1">{
-        var err error
-        for _, s := range c.Series </span><span class="cov8" title="1">{
-                err = s.Validate()
-                if err != nil </span><span class="cov8" title="1">{
-                        return err
-                }</span>
-        }
-        <span class="cov8" title="1">return nil</span>
-}
-
-func (c Chart) getRanges() (xrange, yrange, yrangeAlt Range) <span class="cov8" title="1">{
-        var minx, maxx float64 = math.MaxFloat64, -math.MaxFloat64
-        var miny, maxy float64 = math.MaxFloat64, -math.MaxFloat64
-        var minya, maxya float64 = math.MaxFloat64, -math.MaxFloat64
-
-        seriesMappedToSecondaryAxis := false
-
-        // note: a possible future optimization is to not scan the series values if
-        // all axis are represented by either custom ticks or custom ranges.
-        for _, s := range c.Series </span><span class="cov8" title="1">{
-                if s.GetStyle().IsZero() || s.GetStyle().Show </span><span class="cov8" title="1">{
-                        seriesAxis := s.GetYAxis()
-                        if bvp, isBoundedValuesProvider := s.(BoundedValuesProvider); isBoundedValuesProvider </span><span class="cov0" title="0">{
-                                seriesLength := bvp.Len()
-                                for index := 0; index &lt; seriesLength; index++ </span><span class="cov0" title="0">{
-                                        vx, vy1, vy2 := bvp.GetBoundedValues(index)
-
-                                        minx = math.Min(minx, vx)
-                                        maxx = math.Max(maxx, vx)
-
-                                        if seriesAxis == YAxisPrimary </span><span class="cov0" title="0">{
-                                                miny = math.Min(miny, vy1)
-                                                miny = math.Min(miny, vy2)
-                                                maxy = math.Max(maxy, vy1)
-                                                maxy = math.Max(maxy, vy2)
-                                        }</span> else<span class="cov0" title="0"> if seriesAxis == YAxisSecondary </span><span class="cov0" title="0">{
-                                                minya = math.Min(minya, vy1)
-                                                minya = math.Min(minya, vy2)
-                                                maxya = math.Max(maxya, vy1)
-                                                maxya = math.Max(maxya, vy2)
-                                                seriesMappedToSecondaryAxis = true
-                                        }</span>
-                                }
-                        } else<span class="cov8" title="1"> if vp, isValuesProvider := s.(ValuesProvider); isValuesProvider </span><span class="cov8" title="1">{
-                                seriesLength := vp.Len()
-                                for index := 0; index &lt; seriesLength; index++ </span><span class="cov8" title="1">{
-                                        vx, vy := vp.GetValues(index)
-
-                                        minx = math.Min(minx, vx)
-                                        maxx = math.Max(maxx, vx)
-
-                                        if seriesAxis == YAxisPrimary </span><span class="cov8" title="1">{
-                                                miny = math.Min(miny, vy)
-                                                maxy = math.Max(maxy, vy)
-                                        }</span> else<span class="cov8" title="1"> if seriesAxis == YAxisSecondary </span><span class="cov8" title="1">{
-                                                minya = math.Min(minya, vy)
-                                                maxya = math.Max(maxya, vy)
-                                                seriesMappedToSecondaryAxis = true
-                                        }</span>
-                                }
-                        }
-                }
-        }
-
-        <span class="cov8" title="1">if c.XAxis.Range == nil </span><span class="cov8" title="1">{
-                xrange = &amp;ContinuousRange{}
-        }</span> else<span class="cov8" title="1"> {
-                xrange = c.XAxis.Range
-        }</span>
-
-        <span class="cov8" title="1">if c.YAxis.Range == nil </span><span class="cov8" title="1">{
-                yrange = &amp;ContinuousRange{}
-        }</span> else<span class="cov8" title="1"> {
-                yrange = c.YAxis.Range
-        }</span>
-
-        <span class="cov8" title="1">if c.YAxisSecondary.Range == nil </span><span class="cov8" title="1">{
-                yrangeAlt = &amp;ContinuousRange{}
-        }</span> else<span class="cov8" title="1"> {
-                yrangeAlt = c.YAxisSecondary.Range
-        }</span>
-
-        <span class="cov8" title="1">if len(c.XAxis.Ticks) &gt; 0 </span><span class="cov0" title="0">{
-                tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
-                for _, t := range c.XAxis.Ticks </span><span class="cov0" title="0">{
-                        tickMin = math.Min(tickMin, t.Value)
-                        tickMax = math.Max(tickMax, t.Value)
-                }</span>
-                <span class="cov0" title="0">xrange.SetMin(tickMin)
-                xrange.SetMax(tickMax)</span>
-        } else<span class="cov8" title="1"> if xrange.IsZero() </span><span class="cov8" title="1">{
-                xrange.SetMin(minx)
-                xrange.SetMax(maxx)
-        }</span>
-
-        <span class="cov8" title="1">if len(c.YAxis.Ticks) &gt; 0 </span><span class="cov8" title="1">{
-                tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
-                for _, t := range c.YAxis.Ticks </span><span class="cov8" title="1">{
-                        tickMin = math.Min(tickMin, t.Value)
-                        tickMax = math.Max(tickMax, t.Value)
-                }</span>
-                <span class="cov8" title="1">yrange.SetMin(tickMin)
-                yrange.SetMax(tickMax)</span>
-        } else<span class="cov8" title="1"> if yrange.IsZero() </span><span class="cov8" title="1">{
-                yrange.SetMin(miny)
-                yrange.SetMax(maxy)
-
-                // only round if we're showing the axis
-                if c.YAxis.Style.Show </span><span class="cov0" title="0">{
-                        delta := yrange.GetDelta()
-                        roundTo := util.Math.GetRoundToForDelta(delta)
-                        rmin, rmax := util.Math.RoundDown(yrange.GetMin(), roundTo), util.Math.RoundUp(yrange.GetMax(), roundTo)
-
-                        yrange.SetMin(rmin)
-                        yrange.SetMax(rmax)
-                }</span>
-        }
-
-        <span class="cov8" title="1">if len(c.YAxisSecondary.Ticks) &gt; 0 </span><span class="cov0" title="0">{
-                tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
-                for _, t := range c.YAxis.Ticks </span><span class="cov0" title="0">{
-                        tickMin = math.Min(tickMin, t.Value)
-                        tickMax = math.Max(tickMax, t.Value)
-                }</span>
-                <span class="cov0" title="0">yrangeAlt.SetMin(tickMin)
-                yrangeAlt.SetMax(tickMax)</span>
-        } else<span class="cov8" title="1"> if seriesMappedToSecondaryAxis &amp;&amp; yrangeAlt.IsZero() </span><span class="cov8" title="1">{
-                yrangeAlt.SetMin(minya)
-                yrangeAlt.SetMax(maxya)
-
-                if c.YAxisSecondary.Style.Show </span><span class="cov0" title="0">{
-                        delta := yrangeAlt.GetDelta()
-                        roundTo := util.Math.GetRoundToForDelta(delta)
-                        rmin, rmax := util.Math.RoundDown(yrangeAlt.GetMin(), roundTo), util.Math.RoundUp(yrangeAlt.GetMax(), roundTo)
-                        yrangeAlt.SetMin(rmin)
-                        yrangeAlt.SetMax(rmax)
-                }</span>
-        }
-
-        <span class="cov8" title="1">return</span>
-}
-
-func (c Chart) checkRanges(xr, yr, yra Range) error <span class="cov8" title="1">{
-        xDelta := xr.GetDelta()
-        if math.IsInf(xDelta, 0) </span><span class="cov8" title="1">{
-                return errors.New("infinite x-range delta")
-        }</span>
-        <span class="cov8" title="1">if math.IsNaN(xDelta) </span><span class="cov0" title="0">{
-                return errors.New("nan x-range delta")
-        }</span>
-        <span class="cov8" title="1">if xDelta == 0 </span><span class="cov0" title="0">{
-                return errors.New("zero x-range delta; there needs to be at least (2) values")
-        }</span>
-
-        <span class="cov8" title="1">yDelta := yr.GetDelta()
-        if math.IsInf(yDelta, 0) </span><span class="cov8" title="1">{
-                return errors.New("infinite y-range delta")
-        }</span>
-        <span class="cov8" title="1">if math.IsNaN(yDelta) </span><span class="cov0" title="0">{
-                return errors.New("nan y-range delta")
-        }</span>
-
-        <span class="cov8" title="1">if c.hasSecondarySeries() </span><span class="cov0" title="0">{
-                yraDelta := yra.GetDelta()
-                if math.IsInf(yraDelta, 0) </span><span class="cov0" title="0">{
-                        return errors.New("infinite secondary y-range delta")
-                }</span>
-                <span class="cov0" title="0">if math.IsNaN(yraDelta) </span><span class="cov0" title="0">{
-                        return errors.New("nan secondary y-range delta")
-                }</span>
-        }
-
-        <span class="cov8" title="1">return nil</span>
-}
-
-func (c Chart) getDefaultCanvasBox() Box <span class="cov8" title="1">{
-        return c.Box()
-}</span>
-
-func (c Chart) getValueFormatters() (x, y, ya ValueFormatter) <span class="cov8" title="1">{
-        for _, s := range c.Series </span><span class="cov8" title="1">{
-                if vfp, isVfp := s.(ValueFormatterProvider); isVfp </span><span class="cov8" title="1">{
-                        sx, sy := vfp.GetValueFormatters()
-                        if s.GetYAxis() == YAxisPrimary </span><span class="cov8" title="1">{
-                                x = sx
-                                y = sy
-                        }</span> else<span class="cov8" title="1"> if s.GetYAxis() == YAxisSecondary </span><span class="cov8" title="1">{
-                                x = sx
-                                ya = sy
-                        }</span>
-                }
-        }
-        <span class="cov8" title="1">if c.XAxis.ValueFormatter != nil </span><span class="cov0" title="0">{
-                x = c.XAxis.GetValueFormatter()
-        }</span>
-        <span class="cov8" title="1">if c.YAxis.ValueFormatter != nil </span><span class="cov0" title="0">{
-                y = c.YAxis.GetValueFormatter()
-        }</span>
-        <span class="cov8" title="1">if c.YAxisSecondary.ValueFormatter != nil </span><span class="cov0" title="0">{
-                ya = c.YAxisSecondary.GetValueFormatter()
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-func (c Chart) hasAxes() bool <span class="cov8" title="1">{
-        return c.XAxis.Style.Show || c.YAxis.Style.Show || c.YAxisSecondary.Style.Show
-}</span>
-
-func (c Chart) getAxesTicks(r Renderer, xr, yr, yar Range, xf, yf, yfa ValueFormatter) (xticks, yticks, yticksAlt []Tick) <span class="cov8" title="1">{
-        if c.XAxis.Style.Show </span><span class="cov8" title="1">{
-                xticks = c.XAxis.GetTicks(r, xr, c.styleDefaultsAxes(), xf)
-        }</span>
-        <span class="cov8" title="1">if c.YAxis.Style.Show </span><span class="cov8" title="1">{
-                yticks = c.YAxis.GetTicks(r, yr, c.styleDefaultsAxes(), yf)
-        }</span>
-        <span class="cov8" title="1">if c.YAxisSecondary.Style.Show </span><span class="cov8" title="1">{
-                yticksAlt = c.YAxisSecondary.GetTicks(r, yar, c.styleDefaultsAxes(), yfa)
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-func (c Chart) getAxesAdjustedCanvasBox(r Renderer, canvasBox Box, xr, yr, yra Range, xticks, yticks, yticksAlt []Tick) Box <span class="cov8" title="1">{
-        axesOuterBox := canvasBox.Clone()
-        if c.XAxis.Style.Show </span><span class="cov8" title="1">{
-                axesBounds := c.XAxis.Measure(r, canvasBox, xr, c.styleDefaultsAxes(), xticks)
-                axesOuterBox = axesOuterBox.Grow(axesBounds)
-        }</span>
-        <span class="cov8" title="1">if c.YAxis.Style.Show </span><span class="cov8" title="1">{
-                axesBounds := c.YAxis.Measure(r, canvasBox, yr, c.styleDefaultsAxes(), yticks)
-                axesOuterBox = axesOuterBox.Grow(axesBounds)
-        }</span>
-        <span class="cov8" title="1">if c.YAxisSecondary.Style.Show </span><span class="cov0" title="0">{
-                axesBounds := c.YAxisSecondary.Measure(r, canvasBox, yra, c.styleDefaultsAxes(), yticksAlt)
-                axesOuterBox = axesOuterBox.Grow(axesBounds)
-        }</span>
-
-        <span class="cov8" title="1">return canvasBox.OuterConstrain(c.Box(), axesOuterBox)</span>
-}
-
-func (c Chart) setRangeDomains(canvasBox Box, xr, yr, yra Range) (Range, Range, Range) <span class="cov8" title="1">{
-        xr.SetDomain(canvasBox.Width())
-        yr.SetDomain(canvasBox.Height())
-        yra.SetDomain(canvasBox.Height())
-        return xr, yr, yra
-}</span>
-
-func (c Chart) hasAnnotationSeries() bool <span class="cov8" title="1">{
-        for _, s := range c.Series </span><span class="cov8" title="1">{
-                if as, isAnnotationSeries := s.(AnnotationSeries); isAnnotationSeries </span><span class="cov0" title="0">{
-                        if as.Style.IsZero() || as.Style.Show </span><span class="cov0" title="0">{
-                                return true
-                        }</span>
-                }
-        }
-        <span class="cov8" title="1">return false</span>
-}
-
-func (c Chart) hasSecondarySeries() bool <span class="cov8" title="1">{
-        for _, s := range c.Series </span><span class="cov8" title="1">{
-                if s.GetYAxis() == YAxisSecondary </span><span class="cov0" title="0">{
-                        return true
-                }</span>
-        }
-        <span class="cov8" title="1">return false</span>
-}
-
-func (c Chart) getAnnotationAdjustedCanvasBox(r Renderer, canvasBox Box, xr, yr, yra Range, xf, yf, yfa ValueFormatter) Box <span class="cov0" title="0">{
-        annotationSeriesBox := canvasBox.Clone()
-        for seriesIndex, s := range c.Series </span><span class="cov0" title="0">{
-                if as, isAnnotationSeries := s.(AnnotationSeries); isAnnotationSeries </span><span class="cov0" title="0">{
-                        if as.Style.IsZero() || as.Style.Show </span><span class="cov0" title="0">{
-                                style := c.styleDefaultsSeries(seriesIndex)
-                                var annotationBounds Box
-                                if as.YAxis == YAxisPrimary </span><span class="cov0" title="0">{
-                                        annotationBounds = as.Measure(r, canvasBox, xr, yr, style)
-                                }</span> else<span class="cov0" title="0"> if as.YAxis == YAxisSecondary </span><span class="cov0" title="0">{
-                                        annotationBounds = as.Measure(r, canvasBox, xr, yra, style)
-                                }</span>
-
-                                <span class="cov0" title="0">annotationSeriesBox = annotationSeriesBox.Grow(annotationBounds)</span>
-                        }
-                }
-        }
-
-        <span class="cov0" title="0">return canvasBox.OuterConstrain(c.Box(), annotationSeriesBox)</span>
-}
-
-func (c Chart) getBackgroundStyle() Style <span class="cov8" title="1">{
-        return c.Background.InheritFrom(c.styleDefaultsBackground())
-}</span>
-
-func (c Chart) drawBackground(r Renderer) <span class="cov8" title="1">{
-        Draw.Box(r, Box{
-                Right:  c.GetWidth(),
-                Bottom: c.GetHeight(),
-        }, c.getBackgroundStyle())
-}</span>
-
-func (c Chart) getCanvasStyle() Style <span class="cov8" title="1">{
-        return c.Canvas.InheritFrom(c.styleDefaultsCanvas())
-}</span>
-
-func (c Chart) drawCanvas(r Renderer, canvasBox Box) <span class="cov8" title="1">{
-        Draw.Box(r, canvasBox, c.getCanvasStyle())
-}</span>
-
-func (c Chart) drawAxes(r Renderer, canvasBox Box, xrange, yrange, yrangeAlt Range, xticks, yticks, yticksAlt []Tick) <span class="cov8" title="1">{
-        if c.XAxis.Style.Show </span><span class="cov8" title="1">{
-                c.XAxis.Render(r, canvasBox, xrange, c.styleDefaultsAxes(), xticks)
-        }</span>
-        <span class="cov8" title="1">if c.YAxis.Style.Show </span><span class="cov8" title="1">{
-                c.YAxis.Render(r, canvasBox, yrange, c.styleDefaultsAxes(), yticks)
-        }</span>
-        <span class="cov8" title="1">if c.YAxisSecondary.Style.Show </span><span class="cov0" title="0">{
-                c.YAxisSecondary.Render(r, canvasBox, yrangeAlt, c.styleDefaultsAxes(), yticksAlt)
-        }</span>
-}
-
-func (c Chart) drawSeries(r Renderer, canvasBox Box, xrange, yrange, yrangeAlt Range, s Series, seriesIndex int) <span class="cov8" title="1">{
-        if s.GetStyle().IsZero() || s.GetStyle().Show </span><span class="cov8" title="1">{
-                if s.GetYAxis() == YAxisPrimary </span><span class="cov8" title="1">{
-                        s.Render(r, canvasBox, xrange, yrange, c.styleDefaultsSeries(seriesIndex))
-                }</span> else<span class="cov0" title="0"> if s.GetYAxis() == YAxisSecondary </span><span class="cov0" title="0">{
-                        s.Render(r, canvasBox, xrange, yrangeAlt, c.styleDefaultsSeries(seriesIndex))
-                }</span>
-        }
-}
-
-func (c Chart) drawTitle(r Renderer) <span class="cov8" title="1">{
-        if len(c.Title) &gt; 0 &amp;&amp; c.TitleStyle.Show </span><span class="cov8" title="1">{
-                r.SetFont(c.TitleStyle.GetFont(c.GetFont()))
-                r.SetFontColor(c.TitleStyle.GetFontColor(c.GetColorPalette().TextColor()))
-                titleFontSize := c.TitleStyle.GetFontSize(DefaultTitleFontSize)
-                r.SetFontSize(titleFontSize)
-
-                textBox := r.MeasureText(c.Title)
-
-                textWidth := textBox.Width()
-                textHeight := textBox.Height()
-
-                titleX := (c.GetWidth() &gt;&gt; 1) - (textWidth &gt;&gt; 1)
-                titleY := c.TitleStyle.Padding.GetTop(DefaultTitleTop) + textHeight
-
-                r.Text(c.Title, titleX, titleY)
-        }</span>
-}
-
-func (c Chart) styleDefaultsBackground() Style <span class="cov8" title="1">{
-        return Style{
-                FillColor:   c.GetColorPalette().BackgroundColor(),
-                StrokeColor: c.GetColorPalette().BackgroundStrokeColor(),
-                StrokeWidth: DefaultBackgroundStrokeWidth,
-        }
-}</span>
-
-func (c Chart) styleDefaultsCanvas() Style <span class="cov8" title="1">{
-        return Style{
-                FillColor:   c.GetColorPalette().CanvasColor(),
-                StrokeColor: c.GetColorPalette().CanvasStrokeColor(),
-                StrokeWidth: DefaultCanvasStrokeWidth,
-        }
-}</span>
-
-func (c Chart) styleDefaultsSeries(seriesIndex int) Style <span class="cov8" title="1">{
-        return Style{
-                DotColor:    c.GetColorPalette().GetSeriesColor(seriesIndex),
-                StrokeColor: c.GetColorPalette().GetSeriesColor(seriesIndex),
-                StrokeWidth: DefaultSeriesLineWidth,
-                Font:        c.GetFont(),
-                FontSize:    DefaultFontSize,
-        }
-}</span>
-
-func (c Chart) styleDefaultsAxes() Style <span class="cov8" title="1">{
-        return Style{
-                Font:        c.GetFont(),
-                FontColor:   c.GetColorPalette().TextColor(),
-                FontSize:    DefaultAxisFontSize,
-                StrokeColor: c.GetColorPalette().AxisStrokeColor(),
-                StrokeWidth: DefaultAxisLineWidth,
-        }
-}</span>
-
-func (c Chart) styleDefaultsElements() Style <span class="cov8" title="1">{
-        return Style{
-                Font: c.GetFont(),
-        }
-}</span>
-
-// GetColorPalette returns the color palette for the chart.
-func (c Chart) GetColorPalette() ColorPalette <span class="cov8" title="1">{
-        if c.ColorPalette != nil </span><span class="cov0" title="0">{
-                return c.ColorPalette
-        }</span>
-        <span class="cov8" title="1">return DefaultColorPalette</span>
-}
-
-// Box returns the chart bounds as a box.
-func (c Chart) Box() Box <span class="cov8" title="1">{
-        dpr := c.Background.Padding.GetRight(DefaultBackgroundPadding.Right)
-        dpb := c.Background.Padding.GetBottom(DefaultBackgroundPadding.Bottom)
-
-        return Box{
-                Top:    c.Background.Padding.GetTop(DefaultBackgroundPadding.Top),
-                Left:   c.Background.Padding.GetLeft(DefaultBackgroundPadding.Left),
-                Right:  c.GetWidth() - dpr,
-                Bottom: c.GetHeight() - dpb,
-        }
-}</span>
-</pre>
-		
-		<pre class="file" id="file5" style="display: none">package chart
-
-import "github.com/wcharczuk/go-chart/drawing"
-
-var (
-        // ColorWhite is white.
-        ColorWhite = drawing.Color{R: 255, G: 255, B: 255, A: 255}
-        // ColorBlue is the basic theme blue color.
-        ColorBlue = drawing.Color{R: 0, G: 116, B: 217, A: 255}
-        // ColorCyan is the basic theme cyan color.
-        ColorCyan = drawing.Color{R: 0, G: 217, B: 210, A: 255}
-        // ColorGreen is the basic theme green color.
-        ColorGreen = drawing.Color{R: 0, G: 217, B: 101, A: 255}
-        // ColorRed is the basic theme red color.
-        ColorRed = drawing.Color{R: 217, G: 0, B: 116, A: 255}
-        // ColorOrange is the basic theme orange color.
-        ColorOrange = drawing.Color{R: 217, G: 101, B: 0, A: 255}
-        // ColorYellow is the basic theme yellow color.
-        ColorYellow = drawing.Color{R: 217, G: 210, B: 0, A: 255}
-        // ColorBlack is the basic theme black color.
-        ColorBlack = drawing.Color{R: 51, G: 51, B: 51, A: 255}
-        // ColorLightGray is the basic theme light gray color.
-        ColorLightGray = drawing.Color{R: 239, G: 239, B: 239, A: 255}
-
-        // ColorAlternateBlue is a alternate theme color.
-        ColorAlternateBlue = drawing.Color{R: 106, G: 195, B: 203, A: 255}
-        // ColorAlternateGreen is a alternate theme color.
-        ColorAlternateGreen = drawing.Color{R: 42, G: 190, B: 137, A: 255}
-        // ColorAlternateGray is a alternate theme color.
-        ColorAlternateGray = drawing.Color{R: 110, G: 128, B: 139, A: 255}
-        // ColorAlternateYellow is a alternate theme color.
-        ColorAlternateYellow = drawing.Color{R: 240, G: 174, B: 90, A: 255}
-        // ColorAlternateLightGray is a alternate theme color.
-        ColorAlternateLightGray = drawing.Color{R: 187, G: 190, B: 191, A: 255}
-
-        // ColorTransparent is a transparent (alpha zero) color.
-        ColorTransparent = drawing.Color{R: 1, G: 1, B: 1, A: 0}
-)
-
-var (
-        // DefaultBackgroundColor is the default chart background color.
-        // It is equivalent to css color:white.
-        DefaultBackgroundColor = ColorWhite
-        // DefaultBackgroundStrokeColor is the default chart border color.
-        // It is equivalent to color:white.
-        DefaultBackgroundStrokeColor = ColorWhite
-        // DefaultCanvasColor is the default chart canvas color.
-        // It is equivalent to css color:white.
-        DefaultCanvasColor = ColorWhite
-        // DefaultCanvasStrokeColor is the default chart canvas stroke color.
-        // It is equivalent to css color:white.
-        DefaultCanvasStrokeColor = ColorWhite
-        // DefaultTextColor is the default chart text color.
-        // It is equivalent to #333333.
-        DefaultTextColor = ColorBlack
-        // DefaultAxisColor is the default chart axis line color.
-        // It is equivalent to #333333.
-        DefaultAxisColor = ColorBlack
-        // DefaultStrokeColor is the default chart border color.
-        // It is equivalent to #efefef.
-        DefaultStrokeColor = ColorLightGray
-        // DefaultFillColor is the default fill color.
-        // It is equivalent to #0074d9.
-        DefaultFillColor = ColorBlue
-        // DefaultAnnotationFillColor is the default annotation background color.
-        DefaultAnnotationFillColor = ColorWhite
-        // DefaultGridLineColor is the default grid line color.
-        DefaultGridLineColor = ColorLightGray
-)
-
-var (
-        // DefaultColors are a couple default series colors.
-        DefaultColors = []drawing.Color{
-                ColorBlue,
-                ColorGreen,
-                ColorRed,
-                ColorCyan,
-                ColorOrange,
-        }
-
-        // DefaultAlternateColors are a couple alternate colors.
-        DefaultAlternateColors = []drawing.Color{
-                ColorAlternateBlue,
-                ColorAlternateGreen,
-                ColorAlternateGray,
-                ColorAlternateYellow,
-                ColorBlue,
-                ColorGreen,
-                ColorRed,
-                ColorCyan,
-                ColorOrange,
-        }
-)
-
-// GetDefaultColor returns a color from the default list by index.
-// NOTE: the index will wrap around (using a modulo).
-func GetDefaultColor(index int) drawing.Color <span class="cov8" title="1">{
-        finalIndex := index % len(DefaultColors)
-        return DefaultColors[finalIndex]
-}</span>
-
-// GetAlternateColor returns a color from the default list by index.
-// NOTE: the index will wrap around (using a modulo).
-func GetAlternateColor(index int) drawing.Color <span class="cov8" title="1">{
-        finalIndex := index % len(DefaultAlternateColors)
-        return DefaultAlternateColors[finalIndex]
-}</span>
-
-// ColorPalette is a set of colors that.
-type ColorPalette interface {
-        BackgroundColor() drawing.Color
-        BackgroundStrokeColor() drawing.Color
-        CanvasColor() drawing.Color
-        CanvasStrokeColor() drawing.Color
-        AxisStrokeColor() drawing.Color
-        TextColor() drawing.Color
-        GetSeriesColor(index int) drawing.Color
-}
-
-// DefaultColorPalette represents the default palatte.
-var DefaultColorPalette defaultColorPalette
-
-type defaultColorPalette struct{}
-
-func (dp defaultColorPalette) BackgroundColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultBackgroundColor
-}</span>
-
-func (dp defaultColorPalette) BackgroundStrokeColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultBackgroundStrokeColor
-}</span>
-
-func (dp defaultColorPalette) CanvasColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultCanvasColor
-}</span>
-
-func (dp defaultColorPalette) CanvasStrokeColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultCanvasStrokeColor
-}</span>
-
-func (dp defaultColorPalette) AxisStrokeColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultAxisColor
-}</span>
-
-func (dp defaultColorPalette) TextColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultTextColor
-}</span>
-
-func (dp defaultColorPalette) GetSeriesColor(index int) drawing.Color <span class="cov8" title="1">{
-        return GetDefaultColor(index)
-}</span>
-
-// AlternateColorPalette represents the default palatte.
-var AlternateColorPalette alternateColorPalette
-
-type alternateColorPalette struct{}
-
-func (ap alternateColorPalette) BackgroundColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultBackgroundColor
-}</span>
-
-func (ap alternateColorPalette) BackgroundStrokeColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultBackgroundStrokeColor
-}</span>
-
-func (ap alternateColorPalette) CanvasColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultCanvasColor
-}</span>
-
-func (ap alternateColorPalette) CanvasStrokeColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultCanvasStrokeColor
-}</span>
-
-func (ap alternateColorPalette) AxisStrokeColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultAxisColor
-}</span>
-
-func (ap alternateColorPalette) TextColor() drawing.Color <span class="cov8" title="1">{
-        return DefaultTextColor
-}</span>
-
-func (ap alternateColorPalette) GetSeriesColor(index int) drawing.Color <span class="cov8" title="1">{
-        return GetAlternateColor(index)
-}</span>
-</pre>
-		
-		<pre class="file" id="file6" style="display: none">package chart
-
-// ConcatSeries is a special type of series that concatenates its `InnerSeries`.
-type ConcatSeries []Series
-
-// Len returns the length of the concatenated set of series.
-func (cs ConcatSeries) Len() int <span class="cov8" title="1">{
-        total := 0
-        for _, s := range cs </span><span class="cov8" title="1">{
-                if typed, isValuesProvider := s.(ValuesProvider); isValuesProvider </span><span class="cov8" title="1">{
-                        total += typed.Len()
-                }</span>
-        }
-
-        <span class="cov8" title="1">return total</span>
-}
-
-// GetValue returns the value at the (meta) index (i.e 0 =&gt; totalLen-1)
-func (cs ConcatSeries) GetValue(index int) (x, y float64) <span class="cov8" title="1">{
-        cursor := 0
-        for _, s := range cs </span><span class="cov8" title="1">{
-                if typed, isValuesProvider := s.(ValuesProvider); isValuesProvider </span><span class="cov8" title="1">{
-                        len := typed.Len()
-                        if index &lt; cursor+len </span><span class="cov8" title="1">{
-                                x, y = typed.GetValues(index - cursor) //FENCEPOSTS.
-                                return
-                        }</span>
-                        <span class="cov8" title="1">cursor += typed.Len()</span>
-                }
-        }
-        <span class="cov0" title="0">return</span>
-}
-
-// Validate validates the series.
-func (cs ConcatSeries) Validate() error <span class="cov0" title="0">{
-        var err error
-        for _, s := range cs </span><span class="cov0" title="0">{
-                err = s.Validate()
-                if err != nil </span><span class="cov0" title="0">{
-                        return err
-                }</span>
-        }
-        <span class="cov0" title="0">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file7" style="display: none">package chart
-
-import (
-        "fmt"
-        "math"
-)
-
-// ContinuousRange represents a boundary for a set of numbers.
-type ContinuousRange struct {
-        Min        float64
-        Max        float64
-        Domain     int
-        Descending bool
-}
-
-// IsDescending returns if the range is descending.
-func (r ContinuousRange) IsDescending() bool <span class="cov8" title="1">{
-        return r.Descending
-}</span>
-
-// IsZero returns if the ContinuousRange has been set or not.
-func (r ContinuousRange) IsZero() bool <span class="cov8" title="1">{
-        return (r.Min == 0 || math.IsNaN(r.Min)) &amp;&amp;
-                (r.Max == 0 || math.IsNaN(r.Max)) &amp;&amp;
-                r.Domain == 0
-}</span>
-
-// GetMin gets the min value for the continuous range.
-func (r ContinuousRange) GetMin() float64 <span class="cov8" title="1">{
-        return r.Min
-}</span>
-
-// SetMin sets the min value for the continuous range.
-func (r *ContinuousRange) SetMin(min float64) <span class="cov8" title="1">{
-        r.Min = min
-}</span>
-
-// GetMax returns the max value for the continuous range.
-func (r ContinuousRange) GetMax() float64 <span class="cov8" title="1">{
-        return r.Max
-}</span>
-
-// SetMax sets the max value for the continuous range.
-func (r *ContinuousRange) SetMax(max float64) <span class="cov8" title="1">{
-        r.Max = max
-}</span>
-
-// GetDelta returns the difference between the min and max value.
-func (r ContinuousRange) GetDelta() float64 <span class="cov8" title="1">{
-        return r.Max - r.Min
-}</span>
-
-// GetDomain returns the range domain.
-func (r ContinuousRange) GetDomain() int <span class="cov8" title="1">{
-        return r.Domain
-}</span>
-
-// SetDomain sets the range domain.
-func (r *ContinuousRange) SetDomain(domain int) <span class="cov8" title="1">{
-        r.Domain = domain
-}</span>
-
-// String returns a simple string for the ContinuousRange.
-func (r ContinuousRange) String() string <span class="cov8" title="1">{
-        return fmt.Sprintf("ContinuousRange [%.2f,%.2f] =&gt; %d", r.Min, r.Max, r.Domain)
-}</span>
-
-// Translate maps a given value into the ContinuousRange space.
-func (r ContinuousRange) Translate(value float64) int <span class="cov8" title="1">{
-        normalized := value - r.Min
-        ratio := normalized / r.GetDelta()
-
-        if r.IsDescending() </span><span class="cov0" title="0">{
-                return r.Domain - int(math.Ceil(ratio*float64(r.Domain)))
-        }</span>
-
-        <span class="cov8" title="1">return int(math.Ceil(ratio * float64(r.Domain)))</span>
-}
-</pre>
-		
-		<pre class="file" id="file8" style="display: none">package chart
-
-import "fmt"
-
-// Interface Assertions.
-var (
-        _ Series              = (*ContinuousSeries)(nil)
-        _ FirstValuesProvider = (*ContinuousSeries)(nil)
-        _ LastValuesProvider  = (*ContinuousSeries)(nil)
-)
-
-// ContinuousSeries represents a line on a chart.
-type ContinuousSeries struct {
-        Name  string
-        Style Style
-
-        YAxis YAxisType
-
-        XValueFormatter ValueFormatter
-        YValueFormatter ValueFormatter
-
-        XValues []float64
-        YValues []float64
-}
-
-// GetName returns the name of the time series.
-func (cs ContinuousSeries) GetName() string <span class="cov8" title="1">{
-        return cs.Name
-}</span>
-
-// GetStyle returns the line style.
-func (cs ContinuousSeries) GetStyle() Style <span class="cov8" title="1">{
-        return cs.Style
-}</span>
-
-// Len returns the number of elements in the series.
-func (cs ContinuousSeries) Len() int <span class="cov8" title="1">{
-        return len(cs.XValues)
-}</span>
-
-// GetValues gets the x,y values at a given index.
-func (cs ContinuousSeries) GetValues(index int) (float64, float64) <span class="cov8" title="1">{
-        return cs.XValues[index], cs.YValues[index]
-}</span>
-
-// GetFirstValues gets the first x,y values.
-func (cs ContinuousSeries) GetFirstValues() (float64, float64) <span class="cov8" title="1">{
-        return cs.XValues[0], cs.YValues[0]
-}</span>
-
-// GetLastValues gets the last x,y values.
-func (cs ContinuousSeries) GetLastValues() (float64, float64) <span class="cov8" title="1">{
-        return cs.XValues[len(cs.XValues)-1], cs.YValues[len(cs.YValues)-1]
-}</span>
-
-// GetValueFormatters returns value formatter defaults for the series.
-func (cs ContinuousSeries) GetValueFormatters() (x, y ValueFormatter) <span class="cov8" title="1">{
-        if cs.XValueFormatter != nil </span><span class="cov8" title="1">{
-                x = cs.XValueFormatter
-        }</span> else<span class="cov8" title="1"> {
-                x = FloatValueFormatter
-        }</span>
-        <span class="cov8" title="1">if cs.YValueFormatter != nil </span><span class="cov8" title="1">{
-                y = cs.YValueFormatter
-        }</span> else<span class="cov8" title="1"> {
-                y = FloatValueFormatter
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// GetYAxis returns which YAxis the series draws on.
-func (cs ContinuousSeries) GetYAxis() YAxisType <span class="cov8" title="1">{
-        return cs.YAxis
-}</span>
-
-// Render renders the series.
-func (cs ContinuousSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov8" title="1">{
-        style := cs.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, cs)
-}</span>
-
-// Validate validates the series.
-func (cs ContinuousSeries) Validate() error <span class="cov8" title="1">{
-        if len(cs.XValues) == 0 </span><span class="cov8" title="1">{
-                return fmt.Errorf("continuous series must have xvalues set")
-        }</span>
-
-        <span class="cov8" title="1">if len(cs.YValues) == 0 </span><span class="cov8" title="1">{
-                return fmt.Errorf("continuous series must have yvalues set")
-        }</span>
-        <span class="cov8" title="1">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file9" style="display: none">package chart
-
-import (
-        "math"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-var (
-        // Draw contains helpers for drawing common objects.
-        Draw = &amp;draw{}
-)
-
-type draw struct{}
-
-// LineSeries draws a line series with a renderer.
-func (d draw) LineSeries(r Renderer, canvasBox Box, xrange, yrange Range, style Style, vs ValuesProvider) <span class="cov8" title="1">{
-        if vs.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        <span class="cov8" title="1">cb := canvasBox.Bottom
-        cl := canvasBox.Left
-
-        v0x, v0y := vs.GetValues(0)
-        x0 := cl + xrange.Translate(v0x)
-        y0 := cb - yrange.Translate(v0y)
-
-        yv0 := yrange.Translate(0)
-
-        var vx, vy float64
-        var x, y int
-
-        if style.ShouldDrawStroke() &amp;&amp; style.ShouldDrawFill() </span><span class="cov8" title="1">{
-                style.GetFillOptions().WriteDrawingOptionsToRenderer(r)
-                r.MoveTo(x0, y0)
-                for i := 1; i &lt; vs.Len(); i++ </span><span class="cov8" title="1">{
-                        vx, vy = vs.GetValues(i)
-                        x = cl + xrange.Translate(vx)
-                        y = cb - yrange.Translate(vy)
-                        r.LineTo(x, y)
-                }</span>
-                <span class="cov8" title="1">r.LineTo(x, util.Math.MinInt(cb, cb-yv0))
-                r.LineTo(x0, util.Math.MinInt(cb, cb-yv0))
-                r.LineTo(x0, y0)
-                r.Fill()</span>
-        }
-
-        <span class="cov8" title="1">if style.ShouldDrawStroke() </span><span class="cov8" title="1">{
-                style.GetStrokeOptions().WriteDrawingOptionsToRenderer(r)
-
-                r.MoveTo(x0, y0)
-                for i := 1; i &lt; vs.Len(); i++ </span><span class="cov8" title="1">{
-                        vx, vy = vs.GetValues(i)
-                        x = cl + xrange.Translate(vx)
-                        y = cb - yrange.Translate(vy)
-                        r.LineTo(x, y)
-                }</span>
-                <span class="cov8" title="1">r.Stroke()</span>
-        }
-
-        <span class="cov8" title="1">if style.ShouldDrawDot() </span><span class="cov0" title="0">{
-                defaultDotWidth := style.GetDotWidth()
-
-                style.GetDotOptions().WriteDrawingOptionsToRenderer(r)
-                for i := 0; i &lt; vs.Len(); i++ </span><span class="cov0" title="0">{
-                        vx, vy = vs.GetValues(i)
-                        x = cl + xrange.Translate(vx)
-                        y = cb - yrange.Translate(vy)
-
-                        dotWidth := defaultDotWidth
-                        if style.DotWidthProvider != nil </span><span class="cov0" title="0">{
-                                dotWidth = style.DotWidthProvider(xrange, yrange, i, vx, vy)
-                        }</span>
-
-                        <span class="cov0" title="0">if style.DotColorProvider != nil </span><span class="cov0" title="0">{
-                                dotColor := style.DotColorProvider(xrange, yrange, i, vx, vy)
-
-                                r.SetFillColor(dotColor)
-                                r.SetStrokeColor(dotColor)
-                        }</span>
-
-                        <span class="cov0" title="0">r.Circle(dotWidth, x, y)
-                        r.FillStroke()</span>
-                }
-        }
-}
-
-// BoundedSeries draws a series that implements BoundedValuesProvider.
-func (d draw) BoundedSeries(r Renderer, canvasBox Box, xrange, yrange Range, style Style, bbs BoundedValuesProvider, drawOffsetIndexes ...int) <span class="cov0" title="0">{
-        drawOffsetIndex := 0
-        if len(drawOffsetIndexes) &gt; 0 </span><span class="cov0" title="0">{
-                drawOffsetIndex = drawOffsetIndexes[0]
-        }</span>
-
-        <span class="cov0" title="0">cb := canvasBox.Bottom
-        cl := canvasBox.Left
-
-        v0x, v0y1, v0y2 := bbs.GetBoundedValues(0)
-        x0 := cl + xrange.Translate(v0x)
-        y0 := cb - yrange.Translate(v0y1)
-
-        var vx, vy1, vy2 float64
-        var x, y int
-
-        xvalues := make([]float64, bbs.Len())
-        xvalues[0] = v0x
-        y2values := make([]float64, bbs.Len())
-        y2values[0] = v0y2
-
-        style.GetFillAndStrokeOptions().WriteToRenderer(r)
-        r.MoveTo(x0, y0)
-        for i := 1; i &lt; bbs.Len(); i++ </span><span class="cov0" title="0">{
-                vx, vy1, vy2 = bbs.GetBoundedValues(i)
-
-                xvalues[i] = vx
-                y2values[i] = vy2
-
-                x = cl + xrange.Translate(vx)
-                y = cb - yrange.Translate(vy1)
-                if i &gt; drawOffsetIndex </span><span class="cov0" title="0">{
-                        r.LineTo(x, y)
-                }</span> else<span class="cov0" title="0"> {
-                        r.MoveTo(x, y)
-                }</span>
-        }
-        <span class="cov0" title="0">y = cb - yrange.Translate(vy2)
-        r.LineTo(x, y)
-        for i := bbs.Len() - 1; i &gt;= drawOffsetIndex; i-- </span><span class="cov0" title="0">{
-                vx, vy2 = xvalues[i], y2values[i]
-                x = cl + xrange.Translate(vx)
-                y = cb - yrange.Translate(vy2)
-                r.LineTo(x, y)
-        }</span>
-        <span class="cov0" title="0">r.Close()
-        r.FillStroke()</span>
-}
-
-// HistogramSeries draws a value provider as boxes from 0.
-func (d draw) HistogramSeries(r Renderer, canvasBox Box, xrange, yrange Range, style Style, vs ValuesProvider, barWidths ...int) <span class="cov0" title="0">{
-        if vs.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        //calculate bar width?
-        <span class="cov0" title="0">seriesLength := vs.Len()
-        barWidth := int(math.Floor(float64(xrange.GetDomain()) / float64(seriesLength)))
-        if len(barWidths) &gt; 0 </span><span class="cov0" title="0">{
-                barWidth = barWidths[0]
-        }</span>
-
-        <span class="cov0" title="0">cb := canvasBox.Bottom
-        cl := canvasBox.Left
-
-        //foreach datapoint, draw a box.
-        for index := 0; index &lt; seriesLength; index++ </span><span class="cov0" title="0">{
-                vx, vy := vs.GetValues(index)
-                y0 := yrange.Translate(0)
-                x := cl + xrange.Translate(vx)
-                y := yrange.Translate(vy)
-
-                d.Box(r, Box{
-                        Top:    cb - y0,
-                        Left:   x - (barWidth &gt;&gt; 1),
-                        Right:  x + (barWidth &gt;&gt; 1),
-                        Bottom: cb - y,
-                }, style)
-        }</span>
-}
-
-// MeasureAnnotation measures how big an annotation would be.
-func (d draw) MeasureAnnotation(r Renderer, canvasBox Box, style Style, lx, ly int, label string) Box <span class="cov8" title="1">{
-        style.WriteToRenderer(r)
-        defer r.ResetStyle()
-
-        textBox := r.MeasureText(label)
-        textWidth := textBox.Width()
-        textHeight := textBox.Height()
-        halfTextHeight := textHeight &gt;&gt; 1
-
-        pt := style.Padding.GetTop(DefaultAnnotationPadding.Top)
-        pl := style.Padding.GetLeft(DefaultAnnotationPadding.Left)
-        pr := style.Padding.GetRight(DefaultAnnotationPadding.Right)
-        pb := style.Padding.GetBottom(DefaultAnnotationPadding.Bottom)
-
-        strokeWidth := style.GetStrokeWidth()
-
-        top := ly - (pt + halfTextHeight)
-        right := lx + pl + pr + textWidth + DefaultAnnotationDeltaWidth + int(strokeWidth)
-        bottom := ly + (pb + halfTextHeight)
-
-        return Box{
-                Top:    top,
-                Left:   lx,
-                Right:  right,
-                Bottom: bottom,
-        }
-}</span>
-
-// Annotation draws an anotation with a renderer.
-func (d draw) Annotation(r Renderer, canvasBox Box, style Style, lx, ly int, label string) <span class="cov8" title="1">{
-        style.GetTextOptions().WriteToRenderer(r)
-        defer r.ResetStyle()
-
-        textBox := r.MeasureText(label)
-        textWidth := textBox.Width()
-        halfTextHeight := textBox.Height() &gt;&gt; 1
-
-        style.GetFillAndStrokeOptions().WriteToRenderer(r)
-
-        pt := style.Padding.GetTop(DefaultAnnotationPadding.Top)
-        pl := style.Padding.GetLeft(DefaultAnnotationPadding.Left)
-        pr := style.Padding.GetRight(DefaultAnnotationPadding.Right)
-        pb := style.Padding.GetBottom(DefaultAnnotationPadding.Bottom)
-
-        textX := lx + pl + DefaultAnnotationDeltaWidth
-        textY := ly + halfTextHeight
-
-        ltx := lx + DefaultAnnotationDeltaWidth
-        lty := ly - (pt + halfTextHeight)
-
-        rtx := lx + pl + pr + textWidth + DefaultAnnotationDeltaWidth
-        rty := ly - (pt + halfTextHeight)
-
-        rbx := lx + pl + pr + textWidth + DefaultAnnotationDeltaWidth
-        rby := ly + (pb + halfTextHeight)
-
-        lbx := lx + DefaultAnnotationDeltaWidth
-        lby := ly + (pb + halfTextHeight)
-
-        r.MoveTo(lx, ly)
-        r.LineTo(ltx, lty)
-        r.LineTo(rtx, rty)
-        r.LineTo(rbx, rby)
-        r.LineTo(lbx, lby)
-        r.LineTo(lx, ly)
-        r.Close()
-        r.FillStroke()
-
-        style.GetTextOptions().WriteToRenderer(r)
-        r.Text(label, textX, textY)
-}</span>
-
-// Box draws a box with a given style.
-func (d draw) Box(r Renderer, b Box, s Style) <span class="cov8" title="1">{
-        s.GetFillAndStrokeOptions().WriteToRenderer(r)
-        defer r.ResetStyle()
-
-        r.MoveTo(b.Left, b.Top)
-        r.LineTo(b.Right, b.Top)
-        r.LineTo(b.Right, b.Bottom)
-        r.LineTo(b.Left, b.Bottom)
-        r.LineTo(b.Left, b.Top)
-        r.FillStroke()
-}</span>
-
-func (d draw) BoxRotated(r Renderer, b Box, thetaDegrees float64, s Style) <span class="cov0" title="0">{
-        d.BoxCorners(r, b.Corners().Rotate(thetaDegrees), s)
-}</span>
-
-func (d draw) BoxCorners(r Renderer, bc BoxCorners, s Style) <span class="cov0" title="0">{
-        s.GetFillAndStrokeOptions().WriteToRenderer(r)
-        defer r.ResetStyle()
-
-        r.MoveTo(bc.TopLeft.X, bc.TopLeft.Y)
-        r.LineTo(bc.TopRight.X, bc.TopRight.Y)
-        r.LineTo(bc.BottomRight.X, bc.BottomRight.Y)
-        r.LineTo(bc.BottomLeft.X, bc.BottomLeft.Y)
-        r.Close()
-        r.FillStroke()
-}</span>
-
-// DrawText draws text with a given style.
-func (d draw) Text(r Renderer, text string, x, y int, style Style) <span class="cov8" title="1">{
-        style.GetTextOptions().WriteToRenderer(r)
-        defer r.ResetStyle()
-
-        r.Text(text, x, y)
-}</span>
-
-func (d draw) MeasureText(r Renderer, text string, style Style) Box <span class="cov8" title="1">{
-        style.GetTextOptions().WriteToRenderer(r)
-        defer r.ResetStyle()
-
-        return r.MeasureText(text)
-}</span>
-
-// TextWithin draws the text within a given box.
-func (d draw) TextWithin(r Renderer, text string, box Box, style Style) <span class="cov8" title="1">{
-        style.GetTextOptions().WriteToRenderer(r)
-        defer r.ResetStyle()
-
-        lines := Text.WrapFit(r, text, box.Width(), style)
-        linesBox := Text.MeasureLines(r, lines, style)
-
-        y := box.Top
-
-        switch style.GetTextVerticalAlign() </span>{
-        case TextVerticalAlignBottom, TextVerticalAlignBaseline:<span class="cov0" title="0"> // i have to build better baseline handling into measure text
-                y = y - linesBox.Height()</span>
-        case TextVerticalAlignMiddle, TextVerticalAlignMiddleBaseline:<span class="cov0" title="0">
-                y = (y - linesBox.Height()) &gt;&gt; 1</span>
-        }
-
-        <span class="cov8" title="1">var tx, ty int
-        for _, line := range lines </span><span class="cov8" title="1">{
-                lineBox := r.MeasureText(line)
-                switch style.GetTextHorizontalAlign() </span>{
-                case TextHorizontalAlignCenter:<span class="cov8" title="1">
-                        tx = box.Left + ((box.Width() - lineBox.Width()) &gt;&gt; 1)</span>
-                case TextHorizontalAlignRight:<span class="cov0" title="0">
-                        tx = box.Right - lineBox.Width()</span>
-                default:<span class="cov0" title="0">
-                        tx = box.Left</span>
-                }
-                <span class="cov8" title="1">if style.TextRotationDegrees == 0 </span><span class="cov8" title="1">{
-                        ty = y + lineBox.Height()
-                }</span> else<span class="cov0" title="0"> {
-                        ty = y
-                }</span>
-
-                <span class="cov8" title="1">r.Text(line, tx, ty)
-                y += lineBox.Height() + style.GetTextLineSpacing()</span>
-        }
-}
-</pre>
-		
-		<pre class="file" id="file10" style="display: none">package drawing
-
-import (
-        "fmt"
-        "strconv"
-)
-
-var (
-        // ColorTransparent is a fully transparent color.
-        ColorTransparent = Color{}
-
-        // ColorWhite is white.
-        ColorWhite = Color{R: 255, G: 255, B: 255, A: 255}
-
-        // ColorBlack is black.
-        ColorBlack = Color{R: 0, G: 0, B: 0, A: 255}
-
-        // ColorRed is red.
-        ColorRed = Color{R: 255, G: 0, B: 0, A: 255}
-
-        // ColorGreen is green.
-        ColorGreen = Color{R: 0, G: 255, B: 0, A: 255}
-
-        // ColorBlue is blue.
-        ColorBlue = Color{R: 0, G: 0, B: 255, A: 255}
-)
-
-func parseHex(hex string) uint8 <span class="cov8" title="1">{
-        v, _ := strconv.ParseInt(hex, 16, 16)
-        return uint8(v)
-}</span>
-
-// ColorFromHex returns a color from a css hex code.
-func ColorFromHex(hex string) Color <span class="cov8" title="1">{
-        var c Color
-        if len(hex) == 3 </span><span class="cov8" title="1">{
-                c.R = parseHex(string(hex[0])) * 0x11
-                c.G = parseHex(string(hex[1])) * 0x11
-                c.B = parseHex(string(hex[2])) * 0x11
-        }</span> else<span class="cov8" title="1"> {
-                c.R = parseHex(string(hex[0:2]))
-                c.G = parseHex(string(hex[2:4]))
-                c.B = parseHex(string(hex[4:6]))
-        }</span>
-        <span class="cov8" title="1">c.A = 255
-        return c</span>
-}
-
-// ColorFromAlphaMixedRGBA returns the system alpha mixed rgba values.
-func ColorFromAlphaMixedRGBA(r, g, b, a uint32) Color <span class="cov8" title="1">{
-        fa := float64(a) / 255.0
-        var c Color
-        c.R = uint8(float64(r) / fa)
-        c.G = uint8(float64(g) / fa)
-        c.B = uint8(float64(b) / fa)
-        c.A = uint8(a | (a &gt;&gt; 8))
-        return c
-}</span>
-
-// ColorChannelFromFloat returns a normalized byte from a given float value.
-func ColorChannelFromFloat(v float64) uint8 <span class="cov0" title="0">{
-        return uint8(v * 255)
-}</span>
-
-// Color is our internal color type because color.Color is bullshit.
-type Color struct {
-        R, G, B, A uint8
-}
-
-// RGBA returns the color as a pre-alpha mixed color set.
-func (c Color) RGBA() (r, g, b, a uint32) <span class="cov0" title="0">{
-        fa := float64(c.A) / 255.0
-        r = uint32(float64(uint32(c.R)) * fa)
-        r |= r &lt;&lt; 8
-        g = uint32(float64(uint32(c.G)) * fa)
-        g |= g &lt;&lt; 8
-        b = uint32(float64(uint32(c.B)) * fa)
-        b |= b &lt;&lt; 8
-        a = uint32(c.A)
-        a |= a &lt;&lt; 8
-        return
-}</span>
-
-// IsZero returns if the color has been set or not.
-func (c Color) IsZero() bool <span class="cov0" title="0">{
-        return c.R == 0 &amp;&amp; c.G == 0 &amp;&amp; c.B == 0 &amp;&amp; c.A == 0
-}</span>
-
-// IsTransparent returns if the colors alpha channel is zero.
-func (c Color) IsTransparent() bool <span class="cov0" title="0">{
-        return c.A == 0
-}</span>
-
-// WithAlpha returns a copy of the color with a given alpha.
-func (c Color) WithAlpha(a uint8) Color <span class="cov0" title="0">{
-        return Color{
-                R: c.R,
-                G: c.G,
-                B: c.B,
-                A: a,
-        }
-}</span>
-
-// Equals returns true if the color equals another.
-func (c Color) Equals(other Color) bool <span class="cov8" title="1">{
-        return c.R == other.R &amp;&amp;
-                c.G == other.G &amp;&amp;
-                c.B == other.B &amp;&amp;
-                c.A == other.A
-}</span>
-
-// AverageWith averages two colors.
-func (c Color) AverageWith(other Color) Color <span class="cov0" title="0">{
-        return Color{
-                R: (c.R + other.R) &gt;&gt; 1,
-                G: (c.G + other.G) &gt;&gt; 1,
-                B: (c.B + other.B) &gt;&gt; 1,
-                A: c.A,
-        }
-}</span>
-
-// String returns a css string representation of the color.
-func (c Color) String() string <span class="cov8" title="1">{
-        fa := float64(c.A) / float64(255)
-        return fmt.Sprintf("rgba(%v,%v,%v,%.1f)", c.R, c.G, c.B, fa)
-}</span>
-</pre>
-		
-		<pre class="file" id="file11" style="display: none">package drawing
-
-import "math"
-
-const (
-        // CurveRecursionLimit represents the maximum recursion that is really necessary to subsivide a curve into straight lines
-        CurveRecursionLimit = 32
-)
-
-// Cubic
-//        x1, y1, cpx1, cpy1, cpx2, cpy2, x2, y2 float64
-
-// SubdivideCubic a Bezier cubic curve in 2 equivalents Bezier cubic curves.
-// c1 and c2 parameters are the resulting curves
-func SubdivideCubic(c, c1, c2 []float64) <span class="cov0" title="0">{
-        // First point of c is the first point of c1
-        c1[0], c1[1] = c[0], c[1]
-        // Last point of c is the last point of c2
-        c2[6], c2[7] = c[6], c[7]
-
-        // Subdivide segment using midpoints
-        c1[2] = (c[0] + c[2]) / 2
-        c1[3] = (c[1] + c[3]) / 2
-
-        midX := (c[2] + c[4]) / 2
-        midY := (c[3] + c[5]) / 2
-
-        c2[4] = (c[4] + c[6]) / 2
-        c2[5] = (c[5] + c[7]) / 2
-
-        c1[4] = (c1[2] + midX) / 2
-        c1[5] = (c1[3] + midY) / 2
-
-        c2[2] = (midX + c2[4]) / 2
-        c2[3] = (midY + c2[5]) / 2
-
-        c1[6] = (c1[4] + c2[2]) / 2
-        c1[7] = (c1[5] + c2[3]) / 2
-
-        // Last Point of c1 is equal to the first point of c2
-        c2[0], c2[1] = c1[6], c1[7]
-}</span>
-
-// TraceCubic generate lines subdividing the cubic curve using a Liner
-// flattening_threshold helps determines the flattening expectation of the curve
-func TraceCubic(t Liner, cubic []float64, flatteningThreshold float64) <span class="cov0" title="0">{
-        // Allocation curves
-        var curves [CurveRecursionLimit * 8]float64
-        copy(curves[0:8], cubic[0:8])
-        i := 0
-
-        // current curve
-        var c []float64
-
-        var dx, dy, d2, d3 float64
-
-        for i &gt;= 0 </span><span class="cov0" title="0">{
-                c = curves[i*8:]
-                dx = c[6] - c[0]
-                dy = c[7] - c[1]
-
-                d2 = math.Abs((c[2]-c[6])*dy - (c[3]-c[7])*dx)
-                d3 = math.Abs((c[4]-c[6])*dy - (c[5]-c[7])*dx)
-
-                // if it's flat then trace a line
-                if (d2+d3)*(d2+d3) &lt; flatteningThreshold*(dx*dx+dy*dy) || i == len(curves)-1 </span><span class="cov0" title="0">{
-                        t.LineTo(c[6], c[7])
-                        i--
-                }</span> else<span class="cov0" title="0"> {
-                        // second half of bezier go lower onto the stack
-                        SubdivideCubic(c, curves[(i+1)*8:], curves[i*8:])
-                        i++
-                }</span>
-        }
-}
-
-// Quad
-// x1, y1, cpx1, cpy2, x2, y2 float64
-
-// SubdivideQuad a Bezier quad curve in 2 equivalents Bezier quad curves.
-// c1 and c2 parameters are the resulting curves
-func SubdivideQuad(c, c1, c2 []float64) <span class="cov8" title="1">{
-        // First point of c is the first point of c1
-        c1[0], c1[1] = c[0], c[1]
-        // Last point of c is the last point of c2
-        c2[4], c2[5] = c[4], c[5]
-
-        // Subdivide segment using midpoints
-        c1[2] = (c[0] + c[2]) / 2
-        c1[3] = (c[1] + c[3]) / 2
-        c2[2] = (c[2] + c[4]) / 2
-        c2[3] = (c[3] + c[5]) / 2
-        c1[4] = (c1[2] + c2[2]) / 2
-        c1[5] = (c1[3] + c2[3]) / 2
-        c2[0], c2[1] = c1[4], c1[5]
-        return
-}</span>
-
-func traceWindowIndices(i int) (startAt, endAt int) <span class="cov8" title="1">{
-        startAt = i * 6
-        endAt = startAt + 6
-        return
-}</span>
-
-func traceCalcDeltas(c []float64) (dx, dy, d float64) <span class="cov8" title="1">{
-        dx = c[4] - c[0]
-        dy = c[5] - c[1]
-        d = math.Abs(((c[2]-c[4])*dy - (c[3]-c[5])*dx))
-        return
-}</span>
-
-func traceIsFlat(dx, dy, d, threshold float64) bool <span class="cov8" title="1">{
-        return (d * d) &lt; threshold*(dx*dx+dy*dy)
-}</span>
-
-func traceGetWindow(curves []float64, i int) []float64 <span class="cov8" title="1">{
-        startAt, endAt := traceWindowIndices(i)
-        return curves[startAt:endAt]
-}</span>
-
-// TraceQuad generate lines subdividing the curve using a Liner
-// flattening_threshold helps determines the flattening expectation of the curve
-func TraceQuad(t Liner, quad []float64, flatteningThreshold float64) <span class="cov8" title="1">{
-        const curveLen = CurveRecursionLimit * 6
-        const curveEndIndex = curveLen - 1
-        const lastIteration = CurveRecursionLimit - 1
-
-        // Allocates curves stack
-        curves := make([]float64, curveLen)
-
-        // copy 6 elements from the quad path to the stack
-        copy(curves[0:6], quad[0:6])
-
-        var i int
-        var c []float64
-        var dx, dy, d float64
-
-        for i &gt;= 0 </span><span class="cov8" title="1">{
-                c = traceGetWindow(curves, i)
-                dx, dy, d = traceCalcDeltas(c)
-
-                // bail early if the distance is 0
-                if d == 0 </span><span class="cov0" title="0">{
-                        return
-                }</span>
-
-                // if it's flat then trace a line
-                <span class="cov8" title="1">if traceIsFlat(dx, dy, d, flatteningThreshold) || i == lastIteration </span><span class="cov8" title="1">{
-                        t.LineTo(c[4], c[5])
-                        i--
-                }</span> else<span class="cov8" title="1"> {
-                        SubdivideQuad(c, traceGetWindow(curves, i+1), traceGetWindow(curves, i))
-                        i++
-                }</span>
-        }
-}
-
-// TraceArc trace an arc using a Liner
-func TraceArc(t Liner, x, y, rx, ry, start, angle, scale float64) (lastX, lastY float64) <span class="cov0" title="0">{
-        end := start + angle
-        clockWise := true
-        if angle &lt; 0 </span><span class="cov0" title="0">{
-                clockWise = false
-        }</span>
-        <span class="cov0" title="0">ra := (math.Abs(rx) + math.Abs(ry)) / 2
-        da := math.Acos(ra/(ra+0.125/scale)) * 2
-        //normalize
-        if !clockWise </span><span class="cov0" title="0">{
-                da = -da
-        }</span>
-        <span class="cov0" title="0">angle = start + da
-        var curX, curY float64
-        for </span><span class="cov0" title="0">{
-                if (angle &lt; end-da/4) != clockWise </span><span class="cov0" title="0">{
-                        curX = x + math.Cos(end)*rx
-                        curY = y + math.Sin(end)*ry
-                        return curX, curY
-                }</span>
-                <span class="cov0" title="0">curX = x + math.Cos(angle)*rx
-                curY = y + math.Sin(angle)*ry
-
-                angle += da
-                t.LineTo(curX, curY)</span>
-        }
-}
-</pre>
-		
-		<pre class="file" id="file12" style="display: none">package drawing
-
-// NewDashVertexConverter creates a new dash converter.
-func NewDashVertexConverter(dash []float64, dashOffset float64, flattener Flattener) *DashVertexConverter <span class="cov0" title="0">{
-        var dasher DashVertexConverter
-        dasher.dash = dash
-        dasher.currentDash = 0
-        dasher.dashOffset = dashOffset
-        dasher.next = flattener
-        return &amp;dasher
-}</span>
-
-// DashVertexConverter is a converter for dash vertexes.
-type DashVertexConverter struct {
-        next           Flattener
-        x, y, distance float64
-        dash           []float64
-        currentDash    int
-        dashOffset     float64
-}
-
-// LineTo implements the pathbuilder interface.
-func (dasher *DashVertexConverter) LineTo(x, y float64) <span class="cov0" title="0">{
-        dasher.lineTo(x, y)
-}</span>
-
-// MoveTo implements the pathbuilder interface.
-func (dasher *DashVertexConverter) MoveTo(x, y float64) <span class="cov0" title="0">{
-        dasher.next.MoveTo(x, y)
-        dasher.x, dasher.y = x, y
-        dasher.distance = dasher.dashOffset
-        dasher.currentDash = 0
-}</span>
-
-// LineJoin implements the pathbuilder interface.
-func (dasher *DashVertexConverter) LineJoin() <span class="cov0" title="0">{
-        dasher.next.LineJoin()
-}</span>
-
-// Close implements the pathbuilder interface.
-func (dasher *DashVertexConverter) Close() <span class="cov0" title="0">{
-        dasher.next.Close()
-}</span>
-
-// End implements the pathbuilder interface.
-func (dasher *DashVertexConverter) End() <span class="cov0" title="0">{
-        dasher.next.End()
-}</span>
-
-func (dasher *DashVertexConverter) lineTo(x, y float64) <span class="cov0" title="0">{
-        rest := dasher.dash[dasher.currentDash] - dasher.distance
-        for rest &lt; 0 </span><span class="cov0" title="0">{
-                dasher.distance = dasher.distance - dasher.dash[dasher.currentDash]
-                dasher.currentDash = (dasher.currentDash + 1) % len(dasher.dash)
-                rest = dasher.dash[dasher.currentDash] - dasher.distance
-        }</span>
-        <span class="cov0" title="0">d := distance(dasher.x, dasher.y, x, y)
-        for d &gt;= rest </span><span class="cov0" title="0">{
-                k := rest / d
-                lx := dasher.x + k*(x-dasher.x)
-                ly := dasher.y + k*(y-dasher.y)
-                if dasher.currentDash%2 == 0 </span><span class="cov0" title="0">{
-                        // line
-                        dasher.next.LineTo(lx, ly)
-                }</span> else<span class="cov0" title="0"> {
-                        // gap
-                        dasher.next.End()
-                        dasher.next.MoveTo(lx, ly)
-                }</span>
-                <span class="cov0" title="0">d = d - rest
-                dasher.x, dasher.y = lx, ly
-                dasher.currentDash = (dasher.currentDash + 1) % len(dasher.dash)
-                rest = dasher.dash[dasher.currentDash]</span>
-        }
-        <span class="cov0" title="0">dasher.distance = d
-        if dasher.currentDash%2 == 0 </span><span class="cov0" title="0">{
-                // line
-                dasher.next.LineTo(x, y)
-        }</span> else<span class="cov0" title="0"> {
-                // gap
-                dasher.next.End()
-                dasher.next.MoveTo(x, y)
-        }</span>
-        <span class="cov0" title="0">if dasher.distance &gt;= dasher.dash[dasher.currentDash] </span><span class="cov0" title="0">{
-                dasher.distance = dasher.distance - dasher.dash[dasher.currentDash]
-                dasher.currentDash = (dasher.currentDash + 1) % len(dasher.dash)
-        }</span>
-        <span class="cov0" title="0">dasher.x, dasher.y = x, y</span>
-}
-</pre>
-		
-		<pre class="file" id="file13" style="display: none">package drawing
-
-// DemuxFlattener is a flattener
-type DemuxFlattener struct {
-        Flatteners []Flattener
-}
-
-// MoveTo implements the path builder interface.
-func (dc DemuxFlattener) MoveTo(x, y float64) <span class="cov0" title="0">{
-        for _, flattener := range dc.Flatteners </span><span class="cov0" title="0">{
-                flattener.MoveTo(x, y)
-        }</span>
-}
-
-// LineTo implements the path builder interface.
-func (dc DemuxFlattener) LineTo(x, y float64) <span class="cov0" title="0">{
-        for _, flattener := range dc.Flatteners </span><span class="cov0" title="0">{
-                flattener.LineTo(x, y)
-        }</span>
-}
-
-// LineJoin implements the path builder interface.
-func (dc DemuxFlattener) LineJoin() <span class="cov0" title="0">{
-        for _, flattener := range dc.Flatteners </span><span class="cov0" title="0">{
-                flattener.LineJoin()
-        }</span>
-}
-
-// Close implements the path builder interface.
-func (dc DemuxFlattener) Close() <span class="cov0" title="0">{
-        for _, flattener := range dc.Flatteners </span><span class="cov0" title="0">{
-                flattener.Close()
-        }</span>
-}
-
-// End implements the path builder interface.
-func (dc DemuxFlattener) End() <span class="cov0" title="0">{
-        for _, flattener := range dc.Flatteners </span><span class="cov0" title="0">{
-                flattener.End()
-        }</span>
-}
-</pre>
-		
-		<pre class="file" id="file14" style="display: none">package drawing
-
-// Liner receive segment definition
-type Liner interface {
-        // LineTo Draw a line from the current position to the point (x, y)
-        LineTo(x, y float64)
-}
-
-// Flattener receive segment definition
-type Flattener interface {
-        // MoveTo Start a New line from the point (x, y)
-        MoveTo(x, y float64)
-        // LineTo Draw a line from the current position to the point (x, y)
-        LineTo(x, y float64)
-        // LineJoin add the most recent starting point to close the path to create a polygon
-        LineJoin()
-        // Close add the most recent starting point to close the path to create a polygon
-        Close()
-        // End mark the current line as finished so we can draw caps
-        End()
-}
-
-// Flatten convert curves into straight segments keeping join segments info
-func Flatten(path *Path, flattener Flattener, scale float64) <span class="cov0" title="0">{
-        // First Point
-        var startX, startY float64
-        // Current Point
-        var x, y float64
-        var i int
-        for _, cmp := range path.Components </span><span class="cov0" title="0">{
-                switch cmp </span>{
-                case MoveToComponent:<span class="cov0" title="0">
-                        x, y = path.Points[i], path.Points[i+1]
-                        startX, startY = x, y
-                        if i != 0 </span><span class="cov0" title="0">{
-                                flattener.End()
-                        }</span>
-                        <span class="cov0" title="0">flattener.MoveTo(x, y)
-                        i += 2</span>
-                case LineToComponent:<span class="cov0" title="0">
-                        x, y = path.Points[i], path.Points[i+1]
-                        flattener.LineTo(x, y)
-                        flattener.LineJoin()
-                        i += 2</span>
-                case QuadCurveToComponent:<span class="cov0" title="0">
-                        // we include the previous point for the start of the curve
-                        TraceQuad(flattener, path.Points[i-2:], 0.5)
-                        x, y = path.Points[i+2], path.Points[i+3]
-                        flattener.LineTo(x, y)
-                        i += 4</span>
-                case CubicCurveToComponent:<span class="cov0" title="0">
-                        TraceCubic(flattener, path.Points[i-2:], 0.5)
-                        x, y = path.Points[i+4], path.Points[i+5]
-                        flattener.LineTo(x, y)
-                        i += 6</span>
-                case ArcToComponent:<span class="cov0" title="0">
-                        x, y = TraceArc(flattener, path.Points[i], path.Points[i+1], path.Points[i+2], path.Points[i+3], path.Points[i+4], path.Points[i+5], scale)
-                        flattener.LineTo(x, y)
-                        i += 6</span>
-                case CloseComponent:<span class="cov0" title="0">
-                        flattener.LineTo(startX, startY)
-                        flattener.Close()</span>
-                }
-        }
-        <span class="cov0" title="0">flattener.End()</span>
-}
-
-// SegmentedPath is a path of disparate point sectinos.
-type SegmentedPath struct {
-        Points []float64
-}
-
-// MoveTo implements the path interface.
-func (p *SegmentedPath) MoveTo(x, y float64) <span class="cov0" title="0">{
-        p.Points = append(p.Points, x, y)
-        // TODO need to mark this point as moveto
-}</span>
-
-// LineTo implements the path interface.
-func (p *SegmentedPath) LineTo(x, y float64) <span class="cov0" title="0">{
-        p.Points = append(p.Points, x, y)
-}</span>
-
-// LineJoin implements the path interface.
-func (p *SegmentedPath) LineJoin() {<span class="cov0" title="0">
-        // TODO need to mark the current point as linejoin
-}</span>
-
-// Close implements the path interface.
-func (p *SegmentedPath) Close() {<span class="cov0" title="0">
-        // TODO Close
-}</span>
-
-// End implements the path interface.
-func (p *SegmentedPath) End() {<span class="cov0" title="0">
-        // Nothing to do
-}</span>
-</pre>
-		
-		<pre class="file" id="file15" style="display: none">package drawing
-
-import (
-        "github.com/golang/freetype/raster"
-        "golang.org/x/image/math/fixed"
-)
-
-// FtLineBuilder is a builder for freetype raster glyphs.
-type FtLineBuilder struct {
-        Adder raster.Adder
-}
-
-// MoveTo implements the path builder interface.
-func (liner FtLineBuilder) MoveTo(x, y float64) <span class="cov0" title="0">{
-        liner.Adder.Start(fixed.Point26_6{X: fixed.Int26_6(x * 64), Y: fixed.Int26_6(y * 64)})
-}</span>
-
-// LineTo implements the path builder interface.
-func (liner FtLineBuilder) LineTo(x, y float64) <span class="cov0" title="0">{
-        liner.Adder.Add1(fixed.Point26_6{X: fixed.Int26_6(x * 64), Y: fixed.Int26_6(y * 64)})
-}</span>
-
-// LineJoin implements the path builder interface.
-func (liner FtLineBuilder) LineJoin() {<span class="cov0" title="0">}</span>
-
-// Close implements the path builder interface.
-func (liner FtLineBuilder) Close() {<span class="cov0" title="0">}</span>
-
-// End implements the path builder interface.
-func (liner FtLineBuilder) End() {<span class="cov0" title="0">}</span>
-</pre>
-		
-		<pre class="file" id="file16" style="display: none">package drawing
-
-import (
-        "image/color"
-        "image/draw"
-)
-
-// PolylineBresenham draws a polyline to an image
-func PolylineBresenham(img draw.Image, c color.Color, s ...float64) <span class="cov0" title="0">{
-        for i := 2; i &lt; len(s); i += 2 </span><span class="cov0" title="0">{
-                Bresenham(img, c, int(s[i-2]+0.5), int(s[i-1]+0.5), int(s[i]+0.5), int(s[i+1]+0.5))
-        }</span>
-}
-
-// Bresenham draws a line between (x0, y0) and (x1, y1)
-func Bresenham(img draw.Image, color color.Color, x0, y0, x1, y1 int) <span class="cov0" title="0">{
-        dx := abs(x1 - x0)
-        dy := abs(y1 - y0)
-        var sx, sy int
-        if x0 &lt; x1 </span><span class="cov0" title="0">{
-                sx = 1
-        }</span> else<span class="cov0" title="0"> {
-                sx = -1
-        }</span>
-        <span class="cov0" title="0">if y0 &lt; y1 </span><span class="cov0" title="0">{
-                sy = 1
-        }</span> else<span class="cov0" title="0"> {
-                sy = -1
-        }</span>
-        <span class="cov0" title="0">err := dx - dy
-
-        var e2 int
-        for </span><span class="cov0" title="0">{
-                img.Set(x0, y0, color)
-                if x0 == x1 &amp;&amp; y0 == y1 </span><span class="cov0" title="0">{
-                        return
-                }</span>
-                <span class="cov0" title="0">e2 = 2 * err
-                if e2 &gt; -dy </span><span class="cov0" title="0">{
-                        err = err - dy
-                        x0 = x0 + sx
-                }</span>
-                <span class="cov0" title="0">if e2 &lt; dx </span><span class="cov0" title="0">{
-                        err = err + dx
-                        y0 = y0 + sy
-                }</span>
-        }
-}
-</pre>
-		
-		<pre class="file" id="file17" style="display: none">package drawing
-
-import (
-        "math"
-)
-
-// Matrix represents an affine transformation
-type Matrix [6]float64
-
-const (
-        epsilon = 1e-6
-)
-
-// Determinant compute the determinant of the matrix
-func (tr Matrix) Determinant() float64 <span class="cov0" title="0">{
-        return tr[0]*tr[3] - tr[1]*tr[2]
-}</span>
-
-// Transform applies the transformation matrix to points. It modify the points passed in parameter.
-func (tr Matrix) Transform(points []float64) <span class="cov0" title="0">{
-        for i, j := 0, 1; j &lt; len(points); i, j = i+2, j+2 </span><span class="cov0" title="0">{
-                x := points[i]
-                y := points[j]
-                points[i] = x*tr[0] + y*tr[2] + tr[4]
-                points[j] = x*tr[1] + y*tr[3] + tr[5]
-        }</span>
-}
-
-// TransformPoint applies the transformation matrix to point. It returns the point the transformed point.
-func (tr Matrix) TransformPoint(x, y float64) (xres, yres float64) <span class="cov0" title="0">{
-        xres = x*tr[0] + y*tr[2] + tr[4]
-        yres = x*tr[1] + y*tr[3] + tr[5]
-        return xres, yres
-}</span>
-
-func minMax(x, y float64) (min, max float64) <span class="cov0" title="0">{
-        if x &gt; y </span><span class="cov0" title="0">{
-                return y, x
-        }</span>
-        <span class="cov0" title="0">return x, y</span>
-}
-
-// TransformRectangle applies the transformation matrix to the rectangle represented by the min and the max point of the rectangle
-func (tr Matrix) TransformRectangle(x0, y0, x2, y2 float64) (nx0, ny0, nx2, ny2 float64) <span class="cov0" title="0">{
-        points := []float64{x0, y0, x2, y0, x2, y2, x0, y2}
-        tr.Transform(points)
-        points[0], points[2] = minMax(points[0], points[2])
-        points[4], points[6] = minMax(points[4], points[6])
-        points[1], points[3] = minMax(points[1], points[3])
-        points[5], points[7] = minMax(points[5], points[7])
-
-        nx0 = math.Min(points[0], points[4])
-        ny0 = math.Min(points[1], points[5])
-        nx2 = math.Max(points[2], points[6])
-        ny2 = math.Max(points[3], points[7])
-        return nx0, ny0, nx2, ny2
-}</span>
-
-// InverseTransform applies the transformation inverse matrix to the rectangle represented by the min and the max point of the rectangle
-func (tr Matrix) InverseTransform(points []float64) <span class="cov0" title="0">{
-        d := tr.Determinant() // matrix determinant
-        for i, j := 0, 1; j &lt; len(points); i, j = i+2, j+2 </span><span class="cov0" title="0">{
-                x := points[i]
-                y := points[j]
-                points[i] = ((x-tr[4])*tr[3] - (y-tr[5])*tr[2]) / d
-                points[j] = ((y-tr[5])*tr[0] - (x-tr[4])*tr[1]) / d
-        }</span>
-}
-
-// InverseTransformPoint applies the transformation inverse matrix to point. It returns the point the transformed point.
-func (tr Matrix) InverseTransformPoint(x, y float64) (xres, yres float64) <span class="cov0" title="0">{
-        d := tr.Determinant() // matrix determinant
-        xres = ((x-tr[4])*tr[3] - (y-tr[5])*tr[2]) / d
-        yres = ((y-tr[5])*tr[0] - (x-tr[4])*tr[1]) / d
-        return xres, yres
-}</span>
-
-// VectorTransform applies the transformation matrix to points without using the translation parameter of the affine matrix.
-// It modify the points passed in parameter.
-func (tr Matrix) VectorTransform(points []float64) <span class="cov0" title="0">{
-        for i, j := 0, 1; j &lt; len(points); i, j = i+2, j+2 </span><span class="cov0" title="0">{
-                x := points[i]
-                y := points[j]
-                points[i] = x*tr[0] + y*tr[2]
-                points[j] = x*tr[1] + y*tr[3]
-        }</span>
-}
-
-// NewIdentityMatrix creates an identity transformation matrix.
-func NewIdentityMatrix() Matrix <span class="cov0" title="0">{
-        return Matrix{1, 0, 0, 1, 0, 0}
-}</span>
-
-// NewTranslationMatrix creates a transformation matrix with a translation tx and ty translation parameter
-func NewTranslationMatrix(tx, ty float64) Matrix <span class="cov0" title="0">{
-        return Matrix{1, 0, 0, 1, tx, ty}
-}</span>
-
-// NewScaleMatrix creates a transformation matrix with a sx, sy scale factor
-func NewScaleMatrix(sx, sy float64) Matrix <span class="cov0" title="0">{
-        return Matrix{sx, 0, 0, sy, 0, 0}
-}</span>
-
-// NewRotationMatrix creates a rotation transformation matrix. angle is in radian
-func NewRotationMatrix(angle float64) Matrix <span class="cov0" title="0">{
-        c := math.Cos(angle)
-        s := math.Sin(angle)
-        return Matrix{c, s, -s, c, 0, 0}
-}</span>
-
-// NewMatrixFromRects creates a transformation matrix, combining a scale and a translation, that transform rectangle1 into rectangle2.
-func NewMatrixFromRects(rectangle1, rectangle2 [4]float64) Matrix <span class="cov0" title="0">{
-        xScale := (rectangle2[2] - rectangle2[0]) / (rectangle1[2] - rectangle1[0])
-        yScale := (rectangle2[3] - rectangle2[1]) / (rectangle1[3] - rectangle1[1])
-        xOffset := rectangle2[0] - (rectangle1[0] * xScale)
-        yOffset := rectangle2[1] - (rectangle1[1] * yScale)
-        return Matrix{xScale, 0, 0, yScale, xOffset, yOffset}
-}</span>
-
-// Inverse computes the inverse matrix
-func (tr *Matrix) Inverse() <span class="cov0" title="0">{
-        d := tr.Determinant() // matrix determinant
-        tr0, tr1, tr2, tr3, tr4, tr5 := tr[0], tr[1], tr[2], tr[3], tr[4], tr[5]
-        tr[0] = tr3 / d
-        tr[1] = -tr1 / d
-        tr[2] = -tr2 / d
-        tr[3] = tr0 / d
-        tr[4] = (tr2*tr5 - tr3*tr4) / d
-        tr[5] = (tr1*tr4 - tr0*tr5) / d
-}</span>
-
-// Copy copies the matrix.
-func (tr Matrix) Copy() Matrix <span class="cov0" title="0">{
-        var result Matrix
-        copy(result[:], tr[:])
-        return result
-}</span>
-
-// Compose multiplies trToConcat x tr
-func (tr *Matrix) Compose(trToCompose Matrix) <span class="cov0" title="0">{
-        tr0, tr1, tr2, tr3, tr4, tr5 := tr[0], tr[1], tr[2], tr[3], tr[4], tr[5]
-        tr[0] = trToCompose[0]*tr0 + trToCompose[1]*tr2
-        tr[1] = trToCompose[1]*tr3 + trToCompose[0]*tr1
-        tr[2] = trToCompose[2]*tr0 + trToCompose[3]*tr2
-        tr[3] = trToCompose[3]*tr3 + trToCompose[2]*tr1
-        tr[4] = trToCompose[4]*tr0 + trToCompose[5]*tr2 + tr4
-        tr[5] = trToCompose[5]*tr3 + trToCompose[4]*tr1 + tr5
-}</span>
-
-// Scale adds a scale to the matrix
-func (tr *Matrix) Scale(sx, sy float64) <span class="cov0" title="0">{
-        tr[0] = sx * tr[0]
-        tr[1] = sx * tr[1]
-        tr[2] = sy * tr[2]
-        tr[3] = sy * tr[3]
-}</span>
-
-// Translate adds a translation to the matrix
-func (tr *Matrix) Translate(tx, ty float64) <span class="cov0" title="0">{
-        tr[4] = tx*tr[0] + ty*tr[2] + tr[4]
-        tr[5] = ty*tr[3] + tx*tr[1] + tr[5]
-}</span>
-
-// Rotate adds a rotation to the matrix.
-func (tr *Matrix) Rotate(radians float64) <span class="cov0" title="0">{
-        c := math.Cos(radians)
-        s := math.Sin(radians)
-        t0 := c*tr[0] + s*tr[2]
-        t1 := s*tr[3] + c*tr[1]
-        t2 := c*tr[2] - s*tr[0]
-        t3 := c*tr[3] - s*tr[1]
-        tr[0] = t0
-        tr[1] = t1
-        tr[2] = t2
-        tr[3] = t3
-}</span>
-
-// GetTranslation gets the matrix traslation.
-func (tr Matrix) GetTranslation() (x, y float64) <span class="cov0" title="0">{
-        return tr[4], tr[5]
-}</span>
-
-// GetScaling gets the matrix scaling.
-func (tr Matrix) GetScaling() (x, y float64) <span class="cov0" title="0">{
-        return tr[0], tr[3]
-}</span>
-
-// GetScale computes a scale for the matrix
-func (tr Matrix) GetScale() float64 <span class="cov0" title="0">{
-        x := 0.707106781*tr[0] + 0.707106781*tr[1]
-        y := 0.707106781*tr[2] + 0.707106781*tr[3]
-        return math.Sqrt(x*x + y*y)
-}</span>
-
-// ******************** Testing ********************
-
-// Equals tests if a two transformation are equal. A tolerance is applied when comparing matrix elements.
-func (tr Matrix) Equals(tr2 Matrix) bool <span class="cov0" title="0">{
-        for i := 0; i &lt; 6; i = i + 1 </span><span class="cov0" title="0">{
-                if !fequals(tr[i], tr2[i]) </span><span class="cov0" title="0">{
-                        return false
-                }</span>
-        }
-        <span class="cov0" title="0">return true</span>
-}
-
-// IsIdentity tests if a transformation is the identity transformation. A tolerance is applied when comparing matrix elements.
-func (tr Matrix) IsIdentity() bool <span class="cov0" title="0">{
-        return fequals(tr[4], 0) &amp;&amp; fequals(tr[5], 0) &amp;&amp; tr.IsTranslation()
-}</span>
-
-// IsTranslation tests if a transformation is is a pure translation. A tolerance is applied when comparing matrix elements.
-func (tr Matrix) IsTranslation() bool <span class="cov0" title="0">{
-        return fequals(tr[0], 1) &amp;&amp; fequals(tr[1], 0) &amp;&amp; fequals(tr[2], 0) &amp;&amp; fequals(tr[3], 1)
-}</span>
-
-// fequals compares two floats. return true if the distance between the two floats is less than epsilon, false otherwise
-func fequals(float1, float2 float64) bool <span class="cov0" title="0">{
-        return math.Abs(float1-float2) &lt;= epsilon
-}</span>
-</pre>
-		
-		<pre class="file" id="file18" style="display: none">package drawing
-
-import (
-        "image"
-        "image/color"
-
-        "golang.org/x/image/draw"
-        "golang.org/x/image/math/f64"
-
-        "github.com/golang/freetype/raster"
-)
-
-// Painter implements the freetype raster.Painter and has a SetColor method like the RGBAPainter
-type Painter interface {
-        raster.Painter
-        SetColor(color color.Color)
-}
-
-// DrawImage draws an image into dest using an affine transformation matrix, an op and a filter
-func DrawImage(src image.Image, dest draw.Image, tr Matrix, op draw.Op, filter ImageFilter) <span class="cov0" title="0">{
-        var transformer draw.Transformer
-        switch filter </span>{
-        case LinearFilter:<span class="cov0" title="0">
-                transformer = draw.NearestNeighbor</span>
-        case BilinearFilter:<span class="cov0" title="0">
-                transformer = draw.BiLinear</span>
-        case BicubicFilter:<span class="cov0" title="0">
-                transformer = draw.CatmullRom</span>
-        }
-        <span class="cov0" title="0">transformer.Transform(dest, f64.Aff3{tr[0], tr[1], tr[4], tr[2], tr[3], tr[5]}, src, src.Bounds(), op, nil)</span>
-}
-</pre>
-		
-		<pre class="file" id="file19" style="display: none">package drawing
-
-import (
-        "fmt"
-        "math"
-)
-
-// PathBuilder describes the interface for path drawing.
-type PathBuilder interface {
-        // LastPoint returns the current point of the current sub path
-        LastPoint() (x, y float64)
-        // MoveTo creates a new subpath that start at the specified point
-        MoveTo(x, y float64)
-        // LineTo adds a line to the current subpath
-        LineTo(x, y float64)
-        // QuadCurveTo adds a quadratic Bézier curve to the current subpath
-        QuadCurveTo(cx, cy, x, y float64)
-        // CubicCurveTo adds a cubic Bézier curve to the current subpath
-        CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64)
-        // ArcTo adds an arc to the current subpath
-        ArcTo(cx, cy, rx, ry, startAngle, angle float64)
-        // Close creates a line from the current point to the last MoveTo
-        // point (if not the same) and mark the path as closed so the
-        // first and last lines join nicely.
-        Close()
-}
-
-// PathComponent represents component of a path
-type PathComponent int
-
-const (
-        // MoveToComponent is a MoveTo component in a Path
-        MoveToComponent PathComponent = iota
-        // LineToComponent is a LineTo component in a Path
-        LineToComponent
-        // QuadCurveToComponent is a QuadCurveTo component in a Path
-        QuadCurveToComponent
-        // CubicCurveToComponent is a CubicCurveTo component in a Path
-        CubicCurveToComponent
-        // ArcToComponent is a ArcTo component in a Path
-        ArcToComponent
-        // CloseComponent is a ArcTo component in a Path
-        CloseComponent
-)
-
-// Path stores points
-type Path struct {
-        // Components is a slice of PathComponent in a Path and mark the role of each points in the Path
-        Components []PathComponent
-        // Points are combined with Components to have a specific role in the path
-        Points []float64
-        // Last Point of the Path
-        x, y float64
-}
-
-func (p *Path) appendToPath(cmd PathComponent, points ...float64) <span class="cov0" title="0">{
-        p.Components = append(p.Components, cmd)
-        p.Points = append(p.Points, points...)
-}</span>
-
-// LastPoint returns the current point of the current path
-func (p *Path) LastPoint() (x, y float64) <span class="cov0" title="0">{
-        return p.x, p.y
-}</span>
-
-// MoveTo starts a new path at (x, y) position
-func (p *Path) MoveTo(x, y float64) <span class="cov0" title="0">{
-        p.appendToPath(MoveToComponent, x, y)
-        p.x = x
-        p.y = y
-}</span>
-
-// LineTo adds a line to the current path
-func (p *Path) LineTo(x, y float64) <span class="cov0" title="0">{
-        if len(p.Components) == 0 </span><span class="cov0" title="0">{ //special case when no move has been done
-                p.MoveTo(0, 0)
-        }</span>
-        <span class="cov0" title="0">p.appendToPath(LineToComponent, x, y)
-        p.x = x
-        p.y = y</span>
-}
-
-// QuadCurveTo adds a quadratic bezier curve to the current path
-func (p *Path) QuadCurveTo(cx, cy, x, y float64) <span class="cov0" title="0">{
-        if len(p.Components) == 0 </span><span class="cov0" title="0">{ //special case when no move has been done
-                p.MoveTo(0, 0)
-        }</span>
-        <span class="cov0" title="0">p.appendToPath(QuadCurveToComponent, cx, cy, x, y)
-        p.x = x
-        p.y = y</span>
-}
-
-// CubicCurveTo adds a cubic bezier curve to the current path
-func (p *Path) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) <span class="cov0" title="0">{
-        if len(p.Components) == 0 </span><span class="cov0" title="0">{ //special case when no move has been done
-                p.MoveTo(0, 0)
-        }</span>
-        <span class="cov0" title="0">p.appendToPath(CubicCurveToComponent, cx1, cy1, cx2, cy2, x, y)
-        p.x = x
-        p.y = y</span>
-}
-
-// ArcTo adds an arc to the path
-func (p *Path) ArcTo(cx, cy, rx, ry, startAngle, delta float64) <span class="cov0" title="0">{
-        endAngle := startAngle + delta
-        clockWise := true
-        if delta &lt; 0 </span><span class="cov0" title="0">{
-                clockWise = false
-        }</span>
-        // normalize
-        <span class="cov0" title="0">if clockWise </span><span class="cov0" title="0">{
-                for endAngle &lt; startAngle </span><span class="cov0" title="0">{
-                        endAngle += math.Pi * 2.0
-                }</span>
-        } else<span class="cov0" title="0"> {
-                for startAngle &lt; endAngle </span><span class="cov0" title="0">{
-                        startAngle += math.Pi * 2.0
-                }</span>
-        }
-        <span class="cov0" title="0">startX := cx + math.Cos(startAngle)*rx
-        startY := cy + math.Sin(startAngle)*ry
-        if len(p.Components) &gt; 0 </span><span class="cov0" title="0">{
-                p.LineTo(startX, startY)
-        }</span> else<span class="cov0" title="0"> {
-                p.MoveTo(startX, startY)
-        }</span>
-        <span class="cov0" title="0">p.appendToPath(ArcToComponent, cx, cy, rx, ry, startAngle, delta)
-        p.x = cx + math.Cos(endAngle)*rx
-        p.y = cy + math.Sin(endAngle)*ry</span>
-}
-
-// Close closes the current path
-func (p *Path) Close() <span class="cov0" title="0">{
-        p.appendToPath(CloseComponent)
-}</span>
-
-// Copy make a clone of the current path and return it
-func (p *Path) Copy() (dest *Path) <span class="cov0" title="0">{
-        dest = new(Path)
-        dest.Components = make([]PathComponent, len(p.Components))
-        copy(dest.Components, p.Components)
-        dest.Points = make([]float64, len(p.Points))
-        copy(dest.Points, p.Points)
-        dest.x, dest.y = p.x, p.y
-        return dest
-}</span>
-
-// Clear reset the path
-func (p *Path) Clear() <span class="cov0" title="0">{
-        p.Components = p.Components[0:0]
-        p.Points = p.Points[0:0]
-        return
-}</span>
-
-// IsEmpty returns true if the path is empty
-func (p *Path) IsEmpty() bool <span class="cov0" title="0">{
-        return len(p.Components) == 0
-}</span>
-
-// String returns a debug text view of the path
-func (p *Path) String() string <span class="cov0" title="0">{
-        s := ""
-        j := 0
-        for _, cmd := range p.Components </span><span class="cov0" title="0">{
-                switch cmd </span>{
-                case MoveToComponent:<span class="cov0" title="0">
-                        s += fmt.Sprintf("MoveTo: %f, %f\n", p.Points[j], p.Points[j+1])
-                        j = j + 2</span>
-                case LineToComponent:<span class="cov0" title="0">
-                        s += fmt.Sprintf("LineTo: %f, %f\n", p.Points[j], p.Points[j+1])
-                        j = j + 2</span>
-                case QuadCurveToComponent:<span class="cov0" title="0">
-                        s += fmt.Sprintf("QuadCurveTo: %f, %f, %f, %f\n", p.Points[j], p.Points[j+1], p.Points[j+2], p.Points[j+3])
-                        j = j + 4</span>
-                case CubicCurveToComponent:<span class="cov0" title="0">
-                        s += fmt.Sprintf("CubicCurveTo: %f, %f, %f, %f, %f, %f\n", p.Points[j], p.Points[j+1], p.Points[j+2], p.Points[j+3], p.Points[j+4], p.Points[j+5])
-                        j = j + 6</span>
-                case ArcToComponent:<span class="cov0" title="0">
-                        s += fmt.Sprintf("ArcTo: %f, %f, %f, %f, %f, %f\n", p.Points[j], p.Points[j+1], p.Points[j+2], p.Points[j+3], p.Points[j+4], p.Points[j+5])
-                        j = j + 6</span>
-                case CloseComponent:<span class="cov0" title="0">
-                        s += "Close\n"</span>
-                }
-        }
-        <span class="cov0" title="0">return s</span>
-}
-</pre>
-		
-		<pre class="file" id="file20" style="display: none">package drawing
-
-import (
-        "errors"
-        "image"
-        "image/color"
-        "math"
-
-        "github.com/golang/freetype/raster"
-        "github.com/golang/freetype/truetype"
-        "golang.org/x/image/draw"
-        "golang.org/x/image/font"
-        "golang.org/x/image/math/fixed"
-)
-
-// NewRasterGraphicContext creates a new Graphic context from an image.
-func NewRasterGraphicContext(img draw.Image) (*RasterGraphicContext, error) <span class="cov0" title="0">{
-        var painter Painter
-        switch selectImage := img.(type) </span>{
-        case *image.RGBA:<span class="cov0" title="0">
-                painter = raster.NewRGBAPainter(selectImage)</span>
-        default:<span class="cov0" title="0">
-                return nil, errors.New("NewRasterGraphicContext() :: invalid image type")</span>
-        }
-        <span class="cov0" title="0">return NewRasterGraphicContextWithPainter(img, painter), nil</span>
-}
-
-// NewRasterGraphicContextWithPainter creates a new Graphic context from an image and a Painter (see Freetype-go)
-func NewRasterGraphicContextWithPainter(img draw.Image, painter Painter) *RasterGraphicContext <span class="cov0" title="0">{
-        width, height := img.Bounds().Dx(), img.Bounds().Dy()
-        return &amp;RasterGraphicContext{
-                NewStackGraphicContext(),
-                img,
-                painter,
-                raster.NewRasterizer(width, height),
-                raster.NewRasterizer(width, height),
-                &amp;truetype.GlyphBuf{},
-                DefaultDPI,
-        }
-}</span>
-
-// RasterGraphicContext is the implementation of GraphicContext for a raster image
-type RasterGraphicContext struct {
-        *StackGraphicContext
-        img              draw.Image
-        painter          Painter
-        fillRasterizer   *raster.Rasterizer
-        strokeRasterizer *raster.Rasterizer
-        glyphBuf         *truetype.GlyphBuf
-        DPI              float64
-}
-
-// SetDPI sets the screen resolution in dots per inch.
-func (rgc *RasterGraphicContext) SetDPI(dpi float64) <span class="cov0" title="0">{
-        rgc.DPI = dpi
-        rgc.recalc()
-}</span>
-
-// GetDPI returns the resolution of the Image GraphicContext
-func (rgc *RasterGraphicContext) GetDPI() float64 <span class="cov0" title="0">{
-        return rgc.DPI
-}</span>
-
-// Clear fills the current canvas with a default transparent color
-func (rgc *RasterGraphicContext) Clear() <span class="cov0" title="0">{
-        width, height := rgc.img.Bounds().Dx(), rgc.img.Bounds().Dy()
-        rgc.ClearRect(0, 0, width, height)
-}</span>
-
-// ClearRect fills the current canvas with a default transparent color at the specified rectangle
-func (rgc *RasterGraphicContext) ClearRect(x1, y1, x2, y2 int) <span class="cov0" title="0">{
-        imageColor := image.NewUniform(rgc.current.FillColor)
-        draw.Draw(rgc.img, image.Rect(x1, y1, x2, y2), imageColor, image.ZP, draw.Over)
-}</span>
-
-// DrawImage draws the raster image in the current canvas
-func (rgc *RasterGraphicContext) DrawImage(img image.Image) <span class="cov0" title="0">{
-        DrawImage(img, rgc.img, rgc.current.Tr, draw.Over, BilinearFilter)
-}</span>
-
-// FillString draws the text at point (0, 0)
-func (rgc *RasterGraphicContext) FillString(text string) (cursor float64, err error) <span class="cov0" title="0">{
-        cursor, err = rgc.FillStringAt(text, 0, 0)
-        return
-}</span>
-
-// FillStringAt draws the text at the specified point (x, y)
-func (rgc *RasterGraphicContext) FillStringAt(text string, x, y float64) (cursor float64, err error) <span class="cov0" title="0">{
-        cursor, err = rgc.CreateStringPath(text, x, y)
-        rgc.Fill()
-        return
-}</span>
-
-// StrokeString draws the contour of the text at point (0, 0)
-func (rgc *RasterGraphicContext) StrokeString(text string) (cursor float64, err error) <span class="cov0" title="0">{
-        cursor, err = rgc.StrokeStringAt(text, 0, 0)
-        return
-}</span>
-
-// StrokeStringAt draws the contour of the text at point (x, y)
-func (rgc *RasterGraphicContext) StrokeStringAt(text string, x, y float64) (cursor float64, err error) <span class="cov0" title="0">{
-        cursor, err = rgc.CreateStringPath(text, x, y)
-        rgc.Stroke()
-        return
-}</span>
-
-func (rgc *RasterGraphicContext) drawGlyph(glyph truetype.Index, dx, dy float64) error <span class="cov0" title="0">{
-        if err := rgc.glyphBuf.Load(rgc.current.Font, fixed.Int26_6(rgc.current.Scale), glyph, font.HintingNone); err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-        <span class="cov0" title="0">e0 := 0
-        for _, e1 := range rgc.glyphBuf.Ends </span><span class="cov0" title="0">{
-                DrawContour(rgc, rgc.glyphBuf.Points[e0:e1], dx, dy)
-                e0 = e1
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-
-// CreateStringPath creates a path from the string s at x, y, and returns the string width.
-// The text is placed so that the left edge of the em square of the first character of s
-// and the baseline intersect at x, y. The majority of the affected pixels will be
-// above and to the right of the point, but some may be below or to the left.
-// For example, drawing a string that starts with a 'J' in an italic font may
-// affect pixels below and left of the point.
-func (rgc *RasterGraphicContext) CreateStringPath(s string, x, y float64) (cursor float64, err error) <span class="cov0" title="0">{
-        f := rgc.GetFont()
-        if f == nil </span><span class="cov0" title="0">{
-                err = errors.New("No font loaded, cannot continue")
-                return
-        }</span>
-        <span class="cov0" title="0">rgc.recalc()
-
-        startx := x
-        prev, hasPrev := truetype.Index(0), false
-        for _, rc := range s </span><span class="cov0" title="0">{
-                index := f.Index(rc)
-                if hasPrev </span><span class="cov0" title="0">{
-                        x += fUnitsToFloat64(f.Kern(fixed.Int26_6(rgc.current.Scale), prev, index))
-                }</span>
-                <span class="cov0" title="0">err = rgc.drawGlyph(index, x, y)
-                if err != nil </span><span class="cov0" title="0">{
-                        cursor = x - startx
-                        return
-                }</span>
-                <span class="cov0" title="0">x += fUnitsToFloat64(f.HMetric(fixed.Int26_6(rgc.current.Scale), index).AdvanceWidth)
-                prev, hasPrev = index, true</span>
-        }
-        <span class="cov0" title="0">cursor = x - startx
-        return</span>
-}
-
-// GetStringBounds returns the approximate pixel bounds of a string.
-func (rgc *RasterGraphicContext) GetStringBounds(s string) (left, top, right, bottom float64, err error) <span class="cov0" title="0">{
-        f := rgc.GetFont()
-        if f == nil </span><span class="cov0" title="0">{
-                err = errors.New("No font loaded, cannot continue")
-                return
-        }</span>
-        <span class="cov0" title="0">rgc.recalc()
-
-        left = math.MaxFloat64
-        top = math.MaxFloat64
-
-        cursor := 0.0
-        prev, hasPrev := truetype.Index(0), false
-        for _, rc := range s </span><span class="cov0" title="0">{
-                index := f.Index(rc)
-                if hasPrev </span><span class="cov0" title="0">{
-                        cursor += fUnitsToFloat64(f.Kern(fixed.Int26_6(rgc.current.Scale), prev, index))
-                }</span>
-
-                <span class="cov0" title="0">if err = rgc.glyphBuf.Load(rgc.current.Font, fixed.Int26_6(rgc.current.Scale), index, font.HintingNone); err != nil </span><span class="cov0" title="0">{
-                        return
-                }</span>
-                <span class="cov0" title="0">e0 := 0
-                for _, e1 := range rgc.glyphBuf.Ends </span><span class="cov0" title="0">{
-                        ps := rgc.glyphBuf.Points[e0:e1]
-                        for _, p := range ps </span><span class="cov0" title="0">{
-                                x, y := pointToF64Point(p)
-                                top = math.Min(top, y)
-                                bottom = math.Max(bottom, y)
-                                left = math.Min(left, x+cursor)
-                                right = math.Max(right, x+cursor)
-                        }</span>
-                        <span class="cov0" title="0">e0 = e1</span>
-                }
-                <span class="cov0" title="0">cursor += fUnitsToFloat64(f.HMetric(fixed.Int26_6(rgc.current.Scale), index).AdvanceWidth)
-                prev, hasPrev = index, true</span>
-        }
-        <span class="cov0" title="0">return</span>
-}
-
-// recalc recalculates scale and bounds values from the font size, screen
-// resolution and font metrics, and invalidates the glyph cache.
-func (rgc *RasterGraphicContext) recalc() <span class="cov0" title="0">{
-        rgc.current.Scale = rgc.current.FontSizePoints * float64(rgc.DPI)
-}</span>
-
-// SetFont sets the font used to draw text.
-func (rgc *RasterGraphicContext) SetFont(font *truetype.Font) <span class="cov0" title="0">{
-        rgc.current.Font = font
-}</span>
-
-// GetFont returns the font used to draw text.
-func (rgc *RasterGraphicContext) GetFont() *truetype.Font <span class="cov0" title="0">{
-        return rgc.current.Font
-}</span>
-
-// SetFontSize sets the font size in points (as in ``a 12 point font'').
-func (rgc *RasterGraphicContext) SetFontSize(fontSizePoints float64) <span class="cov0" title="0">{
-        rgc.current.FontSizePoints = fontSizePoints
-        rgc.recalc()
-}</span>
-
-func (rgc *RasterGraphicContext) paint(rasterizer *raster.Rasterizer, color color.Color) <span class="cov0" title="0">{
-        rgc.painter.SetColor(color)
-        rasterizer.Rasterize(rgc.painter)
-        rasterizer.Clear()
-        rgc.current.Path.Clear()
-}</span>
-
-// Stroke strokes the paths with the color specified by SetStrokeColor
-func (rgc *RasterGraphicContext) Stroke(paths ...*Path) <span class="cov0" title="0">{
-        paths = append(paths, rgc.current.Path)
-        rgc.strokeRasterizer.UseNonZeroWinding = true
-
-        stroker := NewLineStroker(rgc.current.Cap, rgc.current.Join, Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.strokeRasterizer}})
-        stroker.HalfLineWidth = rgc.current.LineWidth / 2
-
-        var liner Flattener
-        if rgc.current.Dash != nil &amp;&amp; len(rgc.current.Dash) &gt; 0 </span><span class="cov0" title="0">{
-                liner = NewDashVertexConverter(rgc.current.Dash, rgc.current.DashOffset, stroker)
-        }</span> else<span class="cov0" title="0"> {
-                liner = stroker
-        }</span>
-        <span class="cov0" title="0">for _, p := range paths </span><span class="cov0" title="0">{
-                Flatten(p, liner, rgc.current.Tr.GetScale())
-        }</span>
-
-        <span class="cov0" title="0">rgc.paint(rgc.strokeRasterizer, rgc.current.StrokeColor)</span>
-}
-
-// Fill fills the paths with the color specified by SetFillColor
-func (rgc *RasterGraphicContext) Fill(paths ...*Path) <span class="cov0" title="0">{
-        paths = append(paths, rgc.current.Path)
-        rgc.fillRasterizer.UseNonZeroWinding = rgc.current.FillRule == FillRuleWinding
-
-        flattener := Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.fillRasterizer}}
-        for _, p := range paths </span><span class="cov0" title="0">{
-                Flatten(p, flattener, rgc.current.Tr.GetScale())
-        }</span>
-
-        <span class="cov0" title="0">rgc.paint(rgc.fillRasterizer, rgc.current.FillColor)</span>
-}
-
-// FillStroke first fills the paths and than strokes them
-func (rgc *RasterGraphicContext) FillStroke(paths ...*Path) <span class="cov0" title="0">{
-        paths = append(paths, rgc.current.Path)
-        rgc.fillRasterizer.UseNonZeroWinding = rgc.current.FillRule == FillRuleWinding
-        rgc.strokeRasterizer.UseNonZeroWinding = true
-
-        flattener := Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.fillRasterizer}}
-
-        stroker := NewLineStroker(rgc.current.Cap, rgc.current.Join, Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.strokeRasterizer}})
-        stroker.HalfLineWidth = rgc.current.LineWidth / 2
-
-        var liner Flattener
-        if rgc.current.Dash != nil &amp;&amp; len(rgc.current.Dash) &gt; 0 </span><span class="cov0" title="0">{
-                liner = NewDashVertexConverter(rgc.current.Dash, rgc.current.DashOffset, stroker)
-        }</span> else<span class="cov0" title="0"> {
-                liner = stroker
-        }</span>
-
-        <span class="cov0" title="0">demux := DemuxFlattener{Flatteners: []Flattener{flattener, liner}}
-        for _, p := range paths </span><span class="cov0" title="0">{
-                Flatten(p, demux, rgc.current.Tr.GetScale())
-        }</span>
-
-        // Fill
-        <span class="cov0" title="0">rgc.paint(rgc.fillRasterizer, rgc.current.FillColor)
-        // Stroke
-        rgc.paint(rgc.strokeRasterizer, rgc.current.StrokeColor)</span>
-}
-</pre>
-		
-		<pre class="file" id="file21" style="display: none">package drawing
-
-import (
-        "image"
-        "image/color"
-
-        "github.com/golang/freetype/truetype"
-)
-
-// StackGraphicContext is a context that does thngs.
-type StackGraphicContext struct {
-        current *ContextStack
-}
-
-// ContextStack is a graphic context implementation.
-type ContextStack struct {
-        Tr          Matrix
-        Path        *Path
-        LineWidth   float64
-        Dash        []float64
-        DashOffset  float64
-        StrokeColor color.Color
-        FillColor   color.Color
-        FillRule    FillRule
-        Cap         LineCap
-        Join        LineJoin
-
-        FontSizePoints float64
-        Font           *truetype.Font
-
-        Scale float64
-
-        Previous *ContextStack
-}
-
-// NewStackGraphicContext Create a new Graphic context from an image
-func NewStackGraphicContext() *StackGraphicContext <span class="cov0" title="0">{
-        gc := &amp;StackGraphicContext{}
-        gc.current = new(ContextStack)
-        gc.current.Tr = NewIdentityMatrix()
-        gc.current.Path = new(Path)
-        gc.current.LineWidth = 1.0
-        gc.current.StrokeColor = image.Black
-        gc.current.FillColor = image.White
-        gc.current.Cap = RoundCap
-        gc.current.FillRule = FillRuleEvenOdd
-        gc.current.Join = RoundJoin
-        gc.current.FontSizePoints = 10
-        return gc
-}</span>
-
-// GetMatrixTransform returns the matrix transform.
-func (gc *StackGraphicContext) GetMatrixTransform() Matrix <span class="cov0" title="0">{
-        return gc.current.Tr
-}</span>
-
-// SetMatrixTransform sets the matrix transform.
-func (gc *StackGraphicContext) SetMatrixTransform(tr Matrix) <span class="cov0" title="0">{
-        gc.current.Tr = tr
-}</span>
-
-// ComposeMatrixTransform composes a transform into the current transform.
-func (gc *StackGraphicContext) ComposeMatrixTransform(tr Matrix) <span class="cov0" title="0">{
-        gc.current.Tr.Compose(tr)
-}</span>
-
-// Rotate rotates the matrix transform by an angle in degrees.
-func (gc *StackGraphicContext) Rotate(angle float64) <span class="cov0" title="0">{
-        gc.current.Tr.Rotate(angle)
-}</span>
-
-// Translate translates a transform.
-func (gc *StackGraphicContext) Translate(tx, ty float64) <span class="cov0" title="0">{
-        gc.current.Tr.Translate(tx, ty)
-}</span>
-
-// Scale scales a transform.
-func (gc *StackGraphicContext) Scale(sx, sy float64) <span class="cov0" title="0">{
-        gc.current.Tr.Scale(sx, sy)
-}</span>
-
-// SetStrokeColor sets the stroke color.
-func (gc *StackGraphicContext) SetStrokeColor(c color.Color) <span class="cov0" title="0">{
-        gc.current.StrokeColor = c
-}</span>
-
-// SetFillColor sets the fill color.
-func (gc *StackGraphicContext) SetFillColor(c color.Color) <span class="cov0" title="0">{
-        gc.current.FillColor = c
-}</span>
-
-// SetFillRule sets the fill rule.
-func (gc *StackGraphicContext) SetFillRule(f FillRule) <span class="cov0" title="0">{
-        gc.current.FillRule = f
-}</span>
-
-// SetLineWidth sets the line width.
-func (gc *StackGraphicContext) SetLineWidth(lineWidth float64) <span class="cov0" title="0">{
-        gc.current.LineWidth = lineWidth
-}</span>
-
-// SetLineCap sets the line cap.
-func (gc *StackGraphicContext) SetLineCap(cap LineCap) <span class="cov0" title="0">{
-        gc.current.Cap = cap
-}</span>
-
-// SetLineJoin sets the line join.
-func (gc *StackGraphicContext) SetLineJoin(join LineJoin) <span class="cov0" title="0">{
-        gc.current.Join = join
-}</span>
-
-// SetLineDash sets the line dash.
-func (gc *StackGraphicContext) SetLineDash(dash []float64, dashOffset float64) <span class="cov0" title="0">{
-        gc.current.Dash = dash
-        gc.current.DashOffset = dashOffset
-}</span>
-
-// SetFontSize sets the font size.
-func (gc *StackGraphicContext) SetFontSize(fontSizePoints float64) <span class="cov0" title="0">{
-        gc.current.FontSizePoints = fontSizePoints
-}</span>
-
-// GetFontSize gets the font size.
-func (gc *StackGraphicContext) GetFontSize() float64 <span class="cov0" title="0">{
-        return gc.current.FontSizePoints
-}</span>
-
-// SetFont sets the current font.
-func (gc *StackGraphicContext) SetFont(f *truetype.Font) <span class="cov0" title="0">{
-        gc.current.Font = f
-}</span>
-
-// GetFont returns the font.
-func (gc *StackGraphicContext) GetFont() *truetype.Font <span class="cov0" title="0">{
-        return gc.current.Font
-}</span>
-
-// BeginPath starts a new path.
-func (gc *StackGraphicContext) BeginPath() <span class="cov0" title="0">{
-        gc.current.Path.Clear()
-}</span>
-
-// IsEmpty returns if the path is empty.
-func (gc *StackGraphicContext) IsEmpty() bool <span class="cov0" title="0">{
-        return gc.current.Path.IsEmpty()
-}</span>
-
-// LastPoint returns the last point on the path.
-func (gc *StackGraphicContext) LastPoint() (x float64, y float64) <span class="cov0" title="0">{
-        return gc.current.Path.LastPoint()
-}</span>
-
-// MoveTo moves the cursor for a path.
-func (gc *StackGraphicContext) MoveTo(x, y float64) <span class="cov0" title="0">{
-        gc.current.Path.MoveTo(x, y)
-}</span>
-
-// LineTo draws a line.
-func (gc *StackGraphicContext) LineTo(x, y float64) <span class="cov0" title="0">{
-        gc.current.Path.LineTo(x, y)
-}</span>
-
-// QuadCurveTo draws a quad curve.
-func (gc *StackGraphicContext) QuadCurveTo(cx, cy, x, y float64) <span class="cov0" title="0">{
-        gc.current.Path.QuadCurveTo(cx, cy, x, y)
-}</span>
-
-// CubicCurveTo draws a cubic curve.
-func (gc *StackGraphicContext) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) <span class="cov0" title="0">{
-        gc.current.Path.CubicCurveTo(cx1, cy1, cx2, cy2, x, y)
-}</span>
-
-// ArcTo draws an arc.
-func (gc *StackGraphicContext) ArcTo(cx, cy, rx, ry, startAngle, delta float64) <span class="cov0" title="0">{
-        gc.current.Path.ArcTo(cx, cy, rx, ry, startAngle, delta)
-}</span>
-
-// Close closes a path.
-func (gc *StackGraphicContext) Close() <span class="cov0" title="0">{
-        gc.current.Path.Close()
-}</span>
-
-// Save pushes a context onto the stack.
-func (gc *StackGraphicContext) Save() <span class="cov0" title="0">{
-        context := new(ContextStack)
-        context.FontSizePoints = gc.current.FontSizePoints
-        context.Font = gc.current.Font
-        context.LineWidth = gc.current.LineWidth
-        context.StrokeColor = gc.current.StrokeColor
-        context.FillColor = gc.current.FillColor
-        context.FillRule = gc.current.FillRule
-        context.Dash = gc.current.Dash
-        context.DashOffset = gc.current.DashOffset
-        context.Cap = gc.current.Cap
-        context.Join = gc.current.Join
-        context.Path = gc.current.Path.Copy()
-        context.Font = gc.current.Font
-        context.Scale = gc.current.Scale
-        copy(context.Tr[:], gc.current.Tr[:])
-        context.Previous = gc.current
-        gc.current = context
-}</span>
-
-// Restore restores the previous context.
-func (gc *StackGraphicContext) Restore() <span class="cov0" title="0">{
-        if gc.current.Previous != nil </span><span class="cov0" title="0">{
-                oldContext := gc.current
-                gc.current = gc.current.Previous
-                oldContext.Previous = nil
-        }</span>
-}
-</pre>
-		
-		<pre class="file" id="file22" style="display: none">// Copyright 2010 The draw2d Authors. All rights reserved.
-// created: 13/12/2010 by Laurent Le Goff
-
-package drawing
-
-// NewLineStroker creates a new line stroker.
-func NewLineStroker(c LineCap, j LineJoin, flattener Flattener) *LineStroker <span class="cov0" title="0">{
-        l := new(LineStroker)
-        l.Flattener = flattener
-        l.HalfLineWidth = 0.5
-        l.Cap = c
-        l.Join = j
-        return l
-}</span>
-
-// LineStroker draws the stroke portion of a line.
-type LineStroker struct {
-        Flattener     Flattener
-        HalfLineWidth float64
-        Cap           LineCap
-        Join          LineJoin
-        vertices      []float64
-        rewind        []float64
-        x, y, nx, ny  float64
-}
-
-// MoveTo implements the path builder interface.
-func (l *LineStroker) MoveTo(x, y float64) <span class="cov0" title="0">{
-        l.x, l.y = x, y
-}</span>
-
-// LineTo implements the path builder interface.
-func (l *LineStroker) LineTo(x, y float64) <span class="cov0" title="0">{
-        l.line(l.x, l.y, x, y)
-}</span>
-
-// LineJoin implements the path builder interface.
-func (l *LineStroker) LineJoin() {<span class="cov0" title="0">}</span>
-
-func (l *LineStroker) line(x1, y1, x2, y2 float64) <span class="cov0" title="0">{
-        dx := (x2 - x1)
-        dy := (y2 - y1)
-        d := vectorDistance(dx, dy)
-        if d != 0 </span><span class="cov0" title="0">{
-                nx := dy * l.HalfLineWidth / d
-                ny := -(dx * l.HalfLineWidth / d)
-                l.appendVertex(x1+nx, y1+ny, x2+nx, y2+ny, x1-nx, y1-ny, x2-nx, y2-ny)
-                l.x, l.y, l.nx, l.ny = x2, y2, nx, ny
-        }</span>
-}
-
-// Close implements the path builder interface.
-func (l *LineStroker) Close() <span class="cov0" title="0">{
-        if len(l.vertices) &gt; 1 </span><span class="cov0" title="0">{
-                l.appendVertex(l.vertices[0], l.vertices[1], l.rewind[0], l.rewind[1])
-        }</span>
-}
-
-// End implements the path builder interface.
-func (l *LineStroker) End() <span class="cov0" title="0">{
-        if len(l.vertices) &gt; 1 </span><span class="cov0" title="0">{
-                l.Flattener.MoveTo(l.vertices[0], l.vertices[1])
-                for i, j := 2, 3; j &lt; len(l.vertices); i, j = i+2, j+2 </span><span class="cov0" title="0">{
-                        l.Flattener.LineTo(l.vertices[i], l.vertices[j])
-                }</span>
-        }
-        <span class="cov0" title="0">for i, j := len(l.rewind)-2, len(l.rewind)-1; j &gt; 0; i, j = i-2, j-2 </span><span class="cov0" title="0">{
-                l.Flattener.LineTo(l.rewind[i], l.rewind[j])
-        }</span>
-        <span class="cov0" title="0">if len(l.vertices) &gt; 1 </span><span class="cov0" title="0">{
-                l.Flattener.LineTo(l.vertices[0], l.vertices[1])
-        }</span>
-        <span class="cov0" title="0">l.Flattener.End()
-        // reinit vertices
-        l.vertices = l.vertices[0:0]
-        l.rewind = l.rewind[0:0]
-        l.x, l.y, l.nx, l.ny = 0, 0, 0, 0</span>
-
-}
-
-func (l *LineStroker) appendVertex(vertices ...float64) <span class="cov0" title="0">{
-        s := len(vertices) / 2
-        l.vertices = append(l.vertices, vertices[:s]...)
-        l.rewind = append(l.rewind, vertices[s:]...)
-}</span>
-</pre>
-		
-		<pre class="file" id="file23" style="display: none">package drawing
-
-import (
-        "github.com/golang/freetype/truetype"
-        "golang.org/x/image/math/fixed"
-)
-
-// DrawContour draws the given closed contour at the given sub-pixel offset.
-func DrawContour(path PathBuilder, ps []truetype.Point, dx, dy float64) <span class="cov0" title="0">{
-        if len(ps) == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">startX, startY := pointToF64Point(ps[0])
-        path.MoveTo(startX+dx, startY+dy)
-        q0X, q0Y, on0 := startX, startY, true
-        for _, p := range ps[1:] </span><span class="cov0" title="0">{
-                qX, qY := pointToF64Point(p)
-                on := p.Flags&amp;0x01 != 0
-                if on </span><span class="cov0" title="0">{
-                        if on0 </span><span class="cov0" title="0">{
-                                path.LineTo(qX+dx, qY+dy)
-                        }</span> else<span class="cov0" title="0"> {
-                                path.QuadCurveTo(q0X+dx, q0Y+dy, qX+dx, qY+dy)
-                        }</span>
-                } else<span class="cov0" title="0"> if !on0 </span><span class="cov0" title="0">{
-                        midX := (q0X + qX) / 2
-                        midY := (q0Y + qY) / 2
-                        path.QuadCurveTo(q0X+dx, q0Y+dy, midX+dx, midY+dy)
-                }</span>
-                <span class="cov0" title="0">q0X, q0Y, on0 = qX, qY, on</span>
-        }
-        // Close the curve.
-        <span class="cov0" title="0">if on0 </span><span class="cov0" title="0">{
-                path.LineTo(startX+dx, startY+dy)
-        }</span> else<span class="cov0" title="0"> {
-                path.QuadCurveTo(q0X+dx, q0Y+dy, startX+dx, startY+dy)
-        }</span>
-}
-
-// FontExtents contains font metric information.
-type FontExtents struct {
-        // Ascent is the distance that the text
-        // extends above the baseline.
-        Ascent float64
-
-        // Descent is the distance that the text
-        // extends below the baseline.  The descent
-        // is given as a negative value.
-        Descent float64
-
-        // Height is the distance from the lowest
-        // descending point to the highest ascending
-        // point.
-        Height float64
-}
-
-// Extents returns the FontExtents for a font.
-// TODO needs to read this https://developer.apple.com/fonts/TrueType-Reference-Manual/RM02/Chap2.html#intro
-func Extents(font *truetype.Font, size float64) FontExtents <span class="cov0" title="0">{
-        bounds := font.Bounds(fixed.Int26_6(font.FUnitsPerEm()))
-        scale := size / float64(font.FUnitsPerEm())
-        return FontExtents{
-                Ascent:  float64(bounds.Max.Y) * scale,
-                Descent: float64(bounds.Min.Y) * scale,
-                Height:  float64(bounds.Max.Y-bounds.Min.Y) * scale,
-        }
-}</span>
-</pre>
-		
-		<pre class="file" id="file24" style="display: none">// Copyright 2010 The draw2d Authors. All rights reserved.
-// created: 13/12/2010 by Laurent Le Goff
-
-package drawing
-
-// Transformer apply the Matrix transformation tr
-type Transformer struct {
-        Tr        Matrix
-        Flattener Flattener
-}
-
-// MoveTo implements the path builder interface.
-func (t Transformer) MoveTo(x, y float64) <span class="cov0" title="0">{
-        u := x*t.Tr[0] + y*t.Tr[2] + t.Tr[4]
-        v := x*t.Tr[1] + y*t.Tr[3] + t.Tr[5]
-        t.Flattener.MoveTo(u, v)
-}</span>
-
-// LineTo implements the path builder interface.
-func (t Transformer) LineTo(x, y float64) <span class="cov0" title="0">{
-        u := x*t.Tr[0] + y*t.Tr[2] + t.Tr[4]
-        v := x*t.Tr[1] + y*t.Tr[3] + t.Tr[5]
-        t.Flattener.LineTo(u, v)
-}</span>
-
-// LineJoin implements the path builder interface.
-func (t Transformer) LineJoin() <span class="cov0" title="0">{
-        t.Flattener.LineJoin()
-}</span>
-
-// Close implements the path builder interface.
-func (t Transformer) Close() <span class="cov0" title="0">{
-        t.Flattener.Close()
-}</span>
-
-// End implements the path builder interface.
-func (t Transformer) End() <span class="cov0" title="0">{
-        t.Flattener.End()
-}</span>
-</pre>
-		
-		<pre class="file" id="file25" style="display: none">package drawing
-
-import (
-        "math"
-
-        "golang.org/x/image/math/fixed"
-
-        "github.com/golang/freetype/raster"
-        "github.com/golang/freetype/truetype"
-)
-
-// PixelsToPoints returns the points for a given number of pixels at a DPI.
-func PixelsToPoints(dpi, pixels float64) (points float64) <span class="cov0" title="0">{
-        points = (pixels * 72.0) / dpi
-        return
-}</span>
-
-// PointsToPixels returns the pixels for a given number of points at a DPI.
-func PointsToPixels(dpi, points float64) (pixels float64) <span class="cov0" title="0">{
-        pixels = (points * dpi) / 72.0
-        return
-}</span>
-
-func abs(i int) int <span class="cov0" title="0">{
-        if i &lt; 0 </span><span class="cov0" title="0">{
-                return -i
-        }</span>
-        <span class="cov0" title="0">return i</span>
-}
-
-func distance(x1, y1, x2, y2 float64) float64 <span class="cov0" title="0">{
-        return vectorDistance(x2-x1, y2-y1)
-}</span>
-
-func vectorDistance(dx, dy float64) float64 <span class="cov0" title="0">{
-        return float64(math.Sqrt(dx*dx + dy*dy))
-}</span>
-
-func toFtCap(c LineCap) raster.Capper <span class="cov0" title="0">{
-        switch c </span>{
-        case RoundCap:<span class="cov0" title="0">
-                return raster.RoundCapper</span>
-        case ButtCap:<span class="cov0" title="0">
-                return raster.ButtCapper</span>
-        case SquareCap:<span class="cov0" title="0">
-                return raster.SquareCapper</span>
-        }
-        <span class="cov0" title="0">return raster.RoundCapper</span>
-}
-
-func toFtJoin(j LineJoin) raster.Joiner <span class="cov0" title="0">{
-        switch j </span>{
-        case RoundJoin:<span class="cov0" title="0">
-                return raster.RoundJoiner</span>
-        case BevelJoin:<span class="cov0" title="0">
-                return raster.BevelJoiner</span>
-        }
-        <span class="cov0" title="0">return raster.RoundJoiner</span>
-}
-
-func pointToF64Point(p truetype.Point) (x, y float64) <span class="cov0" title="0">{
-        return fUnitsToFloat64(p.X), -fUnitsToFloat64(p.Y)
-}</span>
-
-func fUnitsToFloat64(x fixed.Int26_6) float64 <span class="cov0" title="0">{
-        scaled := x &lt;&lt; 2
-        return float64(scaled/256) + float64(scaled%256)/256.0
-}</span>
-</pre>
-		
-		<pre class="file" id="file26" style="display: none">package chart
-
-import "fmt"
-
-const (
-        // DefaultEMAPeriod is the default EMA period used in the sigma calculation.
-        DefaultEMAPeriod = 12
-)
-
-// Interface Assertions.
-var (
-        _ Series              = (*EMASeries)(nil)
-        _ FirstValuesProvider = (*EMASeries)(nil)
-        _ LastValuesProvider  = (*EMASeries)(nil)
-)
-
-// EMASeries is a computed series.
-type EMASeries struct {
-        Name  string
-        Style Style
-        YAxis YAxisType
-
-        Period      int
-        InnerSeries ValuesProvider
-
-        cache []float64
-}
-
-// GetName returns the name of the time series.
-func (ema EMASeries) GetName() string <span class="cov0" title="0">{
-        return ema.Name
-}</span>
-
-// GetStyle returns the line style.
-func (ema EMASeries) GetStyle() Style <span class="cov0" title="0">{
-        return ema.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (ema EMASeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return ema.YAxis
-}</span>
-
-// GetPeriod returns the window size.
-func (ema EMASeries) GetPeriod() int <span class="cov8" title="1">{
-        if ema.Period == 0 </span><span class="cov0" title="0">{
-                return DefaultEMAPeriod
-        }</span>
-        <span class="cov8" title="1">return ema.Period</span>
-}
-
-// Len returns the number of elements in the series.
-func (ema EMASeries) Len() int <span class="cov8" title="1">{
-        return ema.InnerSeries.Len()
-}</span>
-
-// GetSigma returns the smoothing factor for the serise.
-func (ema EMASeries) GetSigma() float64 <span class="cov8" title="1">{
-        return 2.0 / (float64(ema.GetPeriod()) + 1)
-}</span>
-
-// GetValues gets a value at a given index.
-func (ema *EMASeries) GetValues(index int) (x, y float64) <span class="cov8" title="1">{
-        if ema.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">if len(ema.cache) == 0 </span><span class="cov8" title="1">{
-                ema.ensureCachedValues()
-        }</span>
-        <span class="cov8" title="1">vx, _ := ema.InnerSeries.GetValues(index)
-        x = vx
-        y = ema.cache[index]
-        return</span>
-}
-
-// GetFirstValues computes the first moving average value.
-func (ema *EMASeries) GetFirstValues() (x, y float64) <span class="cov0" title="0">{
-        if ema.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">if len(ema.cache) == 0 </span><span class="cov0" title="0">{
-                ema.ensureCachedValues()
-        }</span>
-        <span class="cov0" title="0">x, _ = ema.InnerSeries.GetValues(0)
-        y = ema.cache[0]
-        return</span>
-}
-
-// GetLastValues computes the last moving average value but walking back window size samples,
-// and recomputing the last moving average chunk.
-func (ema *EMASeries) GetLastValues() (x, y float64) <span class="cov8" title="1">{
-        if ema.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">if len(ema.cache) == 0 </span><span class="cov0" title="0">{
-                ema.ensureCachedValues()
-        }</span>
-        <span class="cov8" title="1">lastIndex := ema.InnerSeries.Len() - 1
-        x, _ = ema.InnerSeries.GetValues(lastIndex)
-        y = ema.cache[lastIndex]
-        return</span>
-}
-
-func (ema *EMASeries) ensureCachedValues() <span class="cov8" title="1">{
-        seriesLength := ema.InnerSeries.Len()
-        ema.cache = make([]float64, seriesLength)
-        sigma := ema.GetSigma()
-        for x := 0; x &lt; seriesLength; x++ </span><span class="cov8" title="1">{
-                _, y := ema.InnerSeries.GetValues(x)
-                if x == 0 </span><span class="cov8" title="1">{
-                        ema.cache[x] = y
-                        continue</span>
-                }
-                <span class="cov8" title="1">previousEMA := ema.cache[x-1]
-                ema.cache[x] = ((y - previousEMA) * sigma) + previousEMA</span>
-        }
-}
-
-// Render renders the series.
-func (ema *EMASeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := ema.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, ema)
-}</span>
-
-// Validate validates the series.
-func (ema *EMASeries) Validate() error <span class="cov0" title="0">{
-        if ema.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("ema series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file27" style="display: none">package chart
-
-import "fmt"
-
-// FirstValueAnnotation returns an annotation series of just the first value of a value provider as an annotation.
-func FirstValueAnnotation(innerSeries ValuesProvider, vfs ...ValueFormatter) AnnotationSeries <span class="cov8" title="1">{
-        var vf ValueFormatter
-        if len(vfs) &gt; 0 </span><span class="cov0" title="0">{
-                vf = vfs[0]
-        }</span> else<span class="cov8" title="1"> if typed, isTyped := innerSeries.(ValueFormatterProvider); isTyped </span><span class="cov8" title="1">{
-                _, vf = typed.GetValueFormatters()
-        }</span> else<span class="cov0" title="0"> {
-                vf = FloatValueFormatter
-        }</span>
-
-        <span class="cov8" title="1">var firstValue Value2
-        if typed, isTyped := innerSeries.(FirstValuesProvider); isTyped </span><span class="cov8" title="1">{
-                firstValue.XValue, firstValue.YValue = typed.GetFirstValues()
-                firstValue.Label = vf(firstValue.YValue)
-        }</span> else<span class="cov0" title="0"> {
-                firstValue.XValue, firstValue.YValue = innerSeries.GetValues(0)
-                firstValue.Label = vf(firstValue.YValue)
-        }</span>
-
-        <span class="cov8" title="1">var seriesName string
-        var seriesStyle Style
-        if typed, isTyped := innerSeries.(Series); isTyped </span><span class="cov8" title="1">{
-                seriesName = fmt.Sprintf("%s - First Value", typed.GetName())
-                seriesStyle = typed.GetStyle()
-        }</span>
-
-        <span class="cov8" title="1">return AnnotationSeries{
-                Name:        seriesName,
-                Style:       seriesStyle,
-                Annotations: []Value2{firstValue},
-        }</span>
-}
-</pre>
-		
-		<pre class="file" id="file28" style="display: none">package chart
-
-import (
-        "sync"
-
-        "github.com/golang/freetype/truetype"
-        "github.com/wcharczuk/go-chart/roboto"
-)
-
-var (
-        _defaultFontLock sync.Mutex
-        _defaultFont     *truetype.Font
-)
-
-// GetDefaultFont returns the default font (Roboto-Medium).
-func GetDefaultFont() (*truetype.Font, error) <span class="cov8" title="1">{
-        if _defaultFont == nil </span><span class="cov8" title="1">{
-                _defaultFontLock.Lock()
-                defer _defaultFontLock.Unlock()
-                if _defaultFont == nil </span><span class="cov8" title="1">{
-                        font, err := truetype.Parse(roboto.Roboto)
-                        if err != nil </span><span class="cov0" title="0">{
-                                return nil, err
-                        }</span>
-                        <span class="cov8" title="1">_defaultFont = font</span>
-                }
-        }
-        <span class="cov8" title="1">return _defaultFont, nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file29" style="display: none">package chart
-
-// GridLineProvider is a type that provides grid lines.
-type GridLineProvider interface {
-        GetGridLines(ticks []Tick, isVertical bool, majorStyle, minorStyle Style) []GridLine
-}
-
-// GridLine is a line on a graph canvas.
-type GridLine struct {
-        IsMinor bool
-        Style   Style
-        Value   float64
-}
-
-// Major returns if the gridline is a `major` line.
-func (gl GridLine) Major() bool <span class="cov0" title="0">{
-        return !gl.IsMinor
-}</span>
-
-// Minor returns if the gridline is a `minor` line.
-func (gl GridLine) Minor() bool <span class="cov0" title="0">{
-        return gl.IsMinor
-}</span>
-
-// Render renders the gridline
-func (gl GridLine) Render(r Renderer, canvasBox Box, ra Range, isVertical bool, defaults Style) <span class="cov0" title="0">{
-        r.SetStrokeColor(gl.Style.GetStrokeColor(defaults.GetStrokeColor()))
-        r.SetStrokeWidth(gl.Style.GetStrokeWidth(defaults.GetStrokeWidth()))
-        r.SetStrokeDashArray(gl.Style.GetStrokeDashArray(defaults.GetStrokeDashArray()))
-
-        if isVertical </span><span class="cov0" title="0">{
-                lineLeft := canvasBox.Left + ra.Translate(gl.Value)
-                lineBottom := canvasBox.Bottom
-                lineTop := canvasBox.Top
-
-                r.MoveTo(lineLeft, lineBottom)
-                r.LineTo(lineLeft, lineTop)
-                r.Stroke()
-        }</span> else<span class="cov0" title="0"> {
-                lineLeft := canvasBox.Left
-                lineRight := canvasBox.Right
-                lineHeight := canvasBox.Bottom - ra.Translate(gl.Value)
-
-                r.MoveTo(lineLeft, lineHeight)
-                r.LineTo(lineRight, lineHeight)
-                r.Stroke()
-        }</span>
-}
-
-// GenerateGridLines generates grid lines.
-func GenerateGridLines(ticks []Tick, majorStyle, minorStyle Style) []GridLine <span class="cov8" title="1">{
-        var gl []GridLine
-        isMinor := false
-
-        if len(ticks) &lt; 3 </span><span class="cov0" title="0">{
-                return gl
-        }</span>
-
-        <span class="cov8" title="1">for _, t := range ticks[1 : len(ticks)-1] </span><span class="cov8" title="1">{
-                s := majorStyle
-                if isMinor </span><span class="cov8" title="1">{
-                        s = minorStyle
-                }</span>
-                <span class="cov8" title="1">gl = append(gl, GridLine{
-                        Style:   s,
-                        IsMinor: isMinor,
-                        Value:   t.Value,
-                })
-                isMinor = !isMinor</span>
-        }
-        <span class="cov8" title="1">return gl</span>
-}
-</pre>
-		
-		<pre class="file" id="file30" style="display: none">package chart
-
-import "fmt"
-
-// HistogramSeries is a special type of series that draws as a histogram.
-// Some peculiarities; it will always be lower bounded at 0 (at the very least).
-// This may alter ranges a bit and generally you want to put a histogram series on it's own y-axis.
-type HistogramSeries struct {
-        Name        string
-        Style       Style
-        YAxis       YAxisType
-        InnerSeries ValuesProvider
-}
-
-// GetName implements Series.GetName.
-func (hs HistogramSeries) GetName() string <span class="cov0" title="0">{
-        return hs.Name
-}</span>
-
-// GetStyle implements Series.GetStyle.
-func (hs HistogramSeries) GetStyle() Style <span class="cov0" title="0">{
-        return hs.Style
-}</span>
-
-// GetYAxis returns which yaxis the series is mapped to.
-func (hs HistogramSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return hs.YAxis
-}</span>
-
-// Len implements BoundedValuesProvider.Len.
-func (hs HistogramSeries) Len() int <span class="cov8" title="1">{
-        return hs.InnerSeries.Len()
-}</span>
-
-// GetValues implements ValuesProvider.GetValues.
-func (hs HistogramSeries) GetValues(index int) (x, y float64) <span class="cov0" title="0">{
-        return hs.InnerSeries.GetValues(index)
-}</span>
-
-// GetBoundedValues implements BoundedValuesProvider.GetBoundedValue
-func (hs HistogramSeries) GetBoundedValues(index int) (x, y1, y2 float64) <span class="cov8" title="1">{
-        vx, vy := hs.InnerSeries.GetValues(index)
-
-        x = vx
-
-        if vy &gt; 0 </span><span class="cov8" title="1">{
-                y1 = vy
-                return
-        }</span>
-
-        <span class="cov0" title="0">y2 = vy
-        return</span>
-}
-
-// Render implements Series.Render.
-func (hs HistogramSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := hs.Style.InheritFrom(defaults)
-        Draw.HistogramSeries(r, canvasBox, xrange, yrange, style, hs)
-}</span>
-
-// Validate validates the series.
-func (hs HistogramSeries) Validate() error <span class="cov0" title="0">{
-        if hs.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("histogram series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file31" style="display: none">package chart
-
-import (
-        "bytes"
-        "errors"
-        "image"
-        "image/png"
-)
-
-// RGBACollector is a render target for a chart.
-type RGBACollector interface {
-        SetRGBA(i *image.RGBA)
-}
-
-// ImageWriter is a special type of io.Writer that produces a final image.
-type ImageWriter struct {
-        rgba     *image.RGBA
-        contents *bytes.Buffer
-}
-
-func (ir *ImageWriter) Write(buffer []byte) (int, error) <span class="cov0" title="0">{
-        if ir.contents == nil </span><span class="cov0" title="0">{
-                ir.contents = bytes.NewBuffer([]byte{})
-        }</span>
-        <span class="cov0" title="0">return ir.contents.Write(buffer)</span>
-}
-
-// SetRGBA sets a raw version of the image.
-func (ir *ImageWriter) SetRGBA(i *image.RGBA) <span class="cov0" title="0">{
-        ir.rgba = i
-}</span>
-
-// Image returns an *image.Image for the result.
-func (ir *ImageWriter) Image() (image.Image, error) <span class="cov0" title="0">{
-        if ir.rgba != nil </span><span class="cov0" title="0">{
-                return ir.rgba, nil
-        }</span>
-        <span class="cov0" title="0">if ir.contents != nil &amp;&amp; ir.contents.Len() &gt; 0 </span><span class="cov0" title="0">{
-                return png.Decode(ir.contents)
-        }</span>
-        <span class="cov0" title="0">return nil, errors.New("no valid sources for image data, cannot continue")</span>
-}
-</pre>
-		
-		<pre class="file" id="file32" style="display: none">package chart
-
-import "github.com/wcharczuk/go-chart/drawing"
-
-// Jet is a color map provider based on matlab's jet color map.
-func Jet(v, vmin, vmax float64) drawing.Color <span class="cov0" title="0">{
-        c := drawing.Color{R: 0xff, G: 0xff, B: 0xff, A: 0xff} // white
-        var dv float64
-
-        if v &lt; vmin </span><span class="cov0" title="0">{
-                v = vmin
-        }</span>
-        <span class="cov0" title="0">if v &gt; vmax </span><span class="cov0" title="0">{
-                v = vmax
-        }</span>
-        <span class="cov0" title="0">dv = vmax - vmin
-
-        if v &lt; (vmin + 0.25*dv) </span><span class="cov0" title="0">{
-                c.R = 0
-                c.G = drawing.ColorChannelFromFloat(4 * (v - vmin) / dv)
-        }</span> else<span class="cov0" title="0"> if v &lt; (vmin + 0.5*dv) </span><span class="cov0" title="0">{
-                c.R = 0
-                c.B = drawing.ColorChannelFromFloat(1 + 4*(vmin+0.25*dv-v)/dv)
-        }</span> else<span class="cov0" title="0"> if v &lt; (vmin + 0.75*dv) </span><span class="cov0" title="0">{
-                c.R = drawing.ColorChannelFromFloat(4 * (v - vmin - 0.5*dv) / dv)
-                c.B = 0
-        }</span> else<span class="cov0" title="0"> {
-                c.G = drawing.ColorChannelFromFloat(1 + 4*(vmin+0.75*dv-v)/dv)
-                c.B = 0
-        }</span>
-
-        <span class="cov0" title="0">return c</span>
-}
-</pre>
-		
-		<pre class="file" id="file33" style="display: none">package chart
-
-import "fmt"
-
-// LastValueAnnotation returns an annotation series of just the last value of a value provider.
-func LastValueAnnotation(innerSeries ValuesProvider, vfs ...ValueFormatter) AnnotationSeries <span class="cov8" title="1">{
-        var vf ValueFormatter
-        if len(vfs) &gt; 0 </span><span class="cov0" title="0">{
-                vf = vfs[0]
-        }</span> else<span class="cov8" title="1"> if typed, isTyped := innerSeries.(ValueFormatterProvider); isTyped </span><span class="cov8" title="1">{
-                _, vf = typed.GetValueFormatters()
-        }</span> else<span class="cov0" title="0"> {
-                vf = FloatValueFormatter
-        }</span>
-
-        <span class="cov8" title="1">var lastValue Value2
-        if typed, isTyped := innerSeries.(LastValuesProvider); isTyped </span><span class="cov8" title="1">{
-                lastValue.XValue, lastValue.YValue = typed.GetLastValues()
-                lastValue.Label = vf(lastValue.YValue)
-        }</span> else<span class="cov0" title="0"> {
-                lastValue.XValue, lastValue.YValue = innerSeries.GetValues(innerSeries.Len() - 1)
-                lastValue.Label = vf(lastValue.YValue)
-        }</span>
-
-        <span class="cov8" title="1">var seriesName string
-        var seriesStyle Style
-        if typed, isTyped := innerSeries.(Series); isTyped </span><span class="cov8" title="1">{
-                seriesName = fmt.Sprintf("%s - Last Value", typed.GetName())
-                seriesStyle = typed.GetStyle()
-        }</span>
-
-        <span class="cov8" title="1">return AnnotationSeries{
-                Name:        seriesName,
-                Style:       seriesStyle,
-                Annotations: []Value2{lastValue},
-        }</span>
-}
-</pre>
-		
-		<pre class="file" id="file34" style="display: none">package chart
-
-import (
-        "github.com/wcharczuk/go-chart/drawing"
-        "github.com/wcharczuk/go-chart/util"
-)
-
-// Legend returns a legend renderable function.
-func Legend(c *Chart, userDefaults ...Style) Renderable <span class="cov8" title="1">{
-        return func(r Renderer, cb Box, chartDefaults Style) </span><span class="cov8" title="1">{
-                legendDefaults := Style{
-                        FillColor:   drawing.ColorWhite,
-                        FontColor:   DefaultTextColor,
-                        FontSize:    8.0,
-                        StrokeColor: DefaultAxisColor,
-                        StrokeWidth: DefaultAxisLineWidth,
-                }
-
-                var legendStyle Style
-                if len(userDefaults) &gt; 0 </span><span class="cov0" title="0">{
-                        legendStyle = userDefaults[0].InheritFrom(chartDefaults.InheritFrom(legendDefaults))
-                }</span> else<span class="cov8" title="1"> {
-                        legendStyle = chartDefaults.InheritFrom(legendDefaults)
-                }</span>
-
-                // DEFAULTS
-                <span class="cov8" title="1">legendPadding := Box{
-                        Top:    5,
-                        Left:   5,
-                        Right:  5,
-                        Bottom: 5,
-                }
-                lineTextGap := 5
-                lineLengthMinimum := 25
-
-                var labels []string
-                var lines []Style
-                for index, s := range c.Series </span><span class="cov8" title="1">{
-                        if s.GetStyle().IsZero() || s.GetStyle().Show </span><span class="cov8" title="1">{
-                                if _, isAnnotationSeries := s.(AnnotationSeries); !isAnnotationSeries </span><span class="cov8" title="1">{
-                                        labels = append(labels, s.GetName())
-                                        lines = append(lines, s.GetStyle().InheritFrom(c.styleDefaultsSeries(index)))
-                                }</span>
-                        }
-                }
-
-                <span class="cov8" title="1">legend := Box{
-                        Top:  cb.Top,
-                        Left: cb.Left,
-                        // bottom and right will be sized by the legend content + relevant padding.
-                }
-
-                legendContent := Box{
-                        Top:    legend.Top + legendPadding.Top,
-                        Left:   legend.Left + legendPadding.Left,
-                        Right:  legend.Left + legendPadding.Left,
-                        Bottom: legend.Top + legendPadding.Top,
-                }
-
-                legendStyle.GetTextOptions().WriteToRenderer(r)
-
-                // measure
-                labelCount := 0
-                for x := 0; x &lt; len(labels); x++ </span><span class="cov8" title="1">{
-                        if len(labels[x]) &gt; 0 </span><span class="cov8" title="1">{
-                                tb := r.MeasureText(labels[x])
-                                if labelCount &gt; 0 </span><span class="cov0" title="0">{
-                                        legendContent.Bottom += DefaultMinimumTickVerticalSpacing
-                                }</span>
-                                <span class="cov8" title="1">legendContent.Bottom += tb.Height()
-                                right := legendContent.Left + tb.Width() + lineTextGap + lineLengthMinimum
-                                legendContent.Right = util.Math.MaxInt(legendContent.Right, right)
-                                labelCount++</span>
-                        }
-                }
-
-                <span class="cov8" title="1">legend = legend.Grow(legendContent)
-                legend.Right = legendContent.Right + legendPadding.Right
-                legend.Bottom = legendContent.Bottom + legendPadding.Bottom
-
-                Draw.Box(r, legend, legendStyle)
-
-                legendStyle.GetTextOptions().WriteToRenderer(r)
-
-                ycursor := legendContent.Top
-                tx := legendContent.Left
-                legendCount := 0
-                var label string
-                for x := 0; x &lt; len(labels); x++ </span><span class="cov8" title="1">{
-                        label = labels[x]
-                        if len(label) &gt; 0 </span><span class="cov8" title="1">{
-                                if legendCount &gt; 0 </span><span class="cov0" title="0">{
-                                        ycursor += DefaultMinimumTickVerticalSpacing
-                                }</span>
-
-                                <span class="cov8" title="1">tb := r.MeasureText(label)
-
-                                ty := ycursor + tb.Height()
-                                r.Text(label, tx, ty)
-
-                                th2 := tb.Height() &gt;&gt; 1
-
-                                lx := tx + tb.Width() + lineTextGap
-                                ly := ty - th2
-                                lx2 := legendContent.Right - legendPadding.Right
-
-                                r.SetStrokeColor(lines[x].GetStrokeColor())
-                                r.SetStrokeWidth(lines[x].GetStrokeWidth())
-                                r.SetStrokeDashArray(lines[x].GetStrokeDashArray())
-
-                                r.MoveTo(lx, ly)
-                                r.LineTo(lx2, ly)
-                                r.Stroke()
-
-                                ycursor += tb.Height()
-                                legendCount++</span>
-                        }
-                }
-        }
-}
-
-// LegendThin is a legend that doesn't obscure the chart area.
-func LegendThin(c *Chart, userDefaults ...Style) Renderable <span class="cov0" title="0">{
-        return func(r Renderer, cb Box, chartDefaults Style) </span><span class="cov0" title="0">{
-                legendDefaults := Style{
-                        FillColor:   drawing.ColorWhite,
-                        FontColor:   DefaultTextColor,
-                        FontSize:    8.0,
-                        StrokeColor: DefaultAxisColor,
-                        StrokeWidth: DefaultAxisLineWidth,
-                        Padding: Box{
-                                Top:    2,
-                                Left:   7,
-                                Right:  7,
-                                Bottom: 5,
-                        },
-                }
-
-                var legendStyle Style
-                if len(userDefaults) &gt; 0 </span><span class="cov0" title="0">{
-                        legendStyle = userDefaults[0].InheritFrom(chartDefaults.InheritFrom(legendDefaults))
-                }</span> else<span class="cov0" title="0"> {
-                        legendStyle = chartDefaults.InheritFrom(legendDefaults)
-                }</span>
-
-                <span class="cov0" title="0">r.SetFont(legendStyle.GetFont())
-                r.SetFontColor(legendStyle.GetFontColor())
-                r.SetFontSize(legendStyle.GetFontSize())
-
-                var labels []string
-                var lines []Style
-                for index, s := range c.Series </span><span class="cov0" title="0">{
-                        if s.GetStyle().IsZero() || s.GetStyle().Show </span><span class="cov0" title="0">{
-                                if _, isAnnotationSeries := s.(AnnotationSeries); !isAnnotationSeries </span><span class="cov0" title="0">{
-                                        labels = append(labels, s.GetName())
-                                        lines = append(lines, s.GetStyle().InheritFrom(c.styleDefaultsSeries(index)))
-                                }</span>
-                        }
-                }
-
-                <span class="cov0" title="0">var textHeight int
-                var textWidth int
-                var textBox Box
-                for x := 0; x &lt; len(labels); x++ </span><span class="cov0" title="0">{
-                        if len(labels[x]) &gt; 0 </span><span class="cov0" title="0">{
-                                textBox = r.MeasureText(labels[x])
-                                textHeight = util.Math.MaxInt(textBox.Height(), textHeight)
-                                textWidth = util.Math.MaxInt(textBox.Width(), textWidth)
-                        }</span>
-                }
-
-                <span class="cov0" title="0">legendBoxHeight := textHeight + legendStyle.Padding.Top + legendStyle.Padding.Bottom
-                chartPadding := cb.Top
-                legendYMargin := (chartPadding - legendBoxHeight) &gt;&gt; 1
-
-                legendBox := Box{
-                        Left:   cb.Left,
-                        Right:  cb.Right,
-                        Top:    legendYMargin,
-                        Bottom: legendYMargin + legendBoxHeight,
-                }
-
-                Draw.Box(r, legendBox, legendDefaults)
-
-                r.SetFont(legendStyle.GetFont())
-                r.SetFontColor(legendStyle.GetFontColor())
-                r.SetFontSize(legendStyle.GetFontSize())
-
-                lineTextGap := 5
-                lineLengthMinimum := 25
-
-                tx := legendBox.Left + legendStyle.Padding.Left
-                ty := legendYMargin + legendStyle.Padding.Top + textHeight
-                var label string
-                var lx, ly int
-                th2 := textHeight &gt;&gt; 1
-                for index := range labels </span><span class="cov0" title="0">{
-                        label = labels[index]
-                        if len(label) &gt; 0 </span><span class="cov0" title="0">{
-                                textBox = r.MeasureText(label)
-                                r.Text(label, tx, ty)
-
-                                lx = tx + textBox.Width() + lineTextGap
-                                ly = ty - th2
-
-                                r.SetStrokeColor(lines[index].GetStrokeColor())
-                                r.SetStrokeWidth(lines[index].GetStrokeWidth())
-                                r.SetStrokeDashArray(lines[index].GetStrokeDashArray())
-
-                                r.MoveTo(lx, ly)
-                                r.LineTo(lx+lineLengthMinimum, ly)
-                                r.Stroke()
-
-                                tx += textBox.Width() + DefaultMinimumTickHorizontalSpacing + lineTextGap + lineLengthMinimum
-                        }</span>
-                }
-        }
-}
-
-// LegendLeft is a legend that is designed for longer series lists.
-func LegendLeft(c *Chart, userDefaults ...Style) Renderable <span class="cov0" title="0">{
-        return func(r Renderer, cb Box, chartDefaults Style) </span><span class="cov0" title="0">{
-                legendDefaults := Style{
-                        FillColor:   drawing.ColorWhite,
-                        FontColor:   DefaultTextColor,
-                        FontSize:    8.0,
-                        StrokeColor: DefaultAxisColor,
-                        StrokeWidth: DefaultAxisLineWidth,
-                }
-
-                var legendStyle Style
-                if len(userDefaults) &gt; 0 </span><span class="cov0" title="0">{
-                        legendStyle = userDefaults[0].InheritFrom(chartDefaults.InheritFrom(legendDefaults))
-                }</span> else<span class="cov0" title="0"> {
-                        legendStyle = chartDefaults.InheritFrom(legendDefaults)
-                }</span>
-
-                // DEFAULTS
-                <span class="cov0" title="0">legendPadding := Box{
-                        Top:    5,
-                        Left:   5,
-                        Right:  5,
-                        Bottom: 5,
-                }
-                lineTextGap := 5
-                lineLengthMinimum := 25
-
-                var labels []string
-                var lines []Style
-                for index, s := range c.Series </span><span class="cov0" title="0">{
-                        if s.GetStyle().IsZero() || s.GetStyle().Show </span><span class="cov0" title="0">{
-                                if _, isAnnotationSeries := s.(AnnotationSeries); !isAnnotationSeries </span><span class="cov0" title="0">{
-                                        labels = append(labels, s.GetName())
-                                        lines = append(lines, s.GetStyle().InheritFrom(c.styleDefaultsSeries(index)))
-                                }</span>
-                        }
-                }
-
-                <span class="cov0" title="0">legend := Box{
-                        Top:  5,
-                        Left: 5,
-                        // bottom and right will be sized by the legend content + relevant padding.
-                }
-
-                legendContent := Box{
-                        Top:    legend.Top + legendPadding.Top,
-                        Left:   legend.Left + legendPadding.Left,
-                        Right:  legend.Left + legendPadding.Left,
-                        Bottom: legend.Top + legendPadding.Top,
-                }
-
-                legendStyle.GetTextOptions().WriteToRenderer(r)
-
-                // measure
-                labelCount := 0
-                for x := 0; x &lt; len(labels); x++ </span><span class="cov0" title="0">{
-                        if len(labels[x]) &gt; 0 </span><span class="cov0" title="0">{
-                                tb := r.MeasureText(labels[x])
-                                if labelCount &gt; 0 </span><span class="cov0" title="0">{
-                                        legendContent.Bottom += DefaultMinimumTickVerticalSpacing
-                                }</span>
-                                <span class="cov0" title="0">legendContent.Bottom += tb.Height()
-                                right := legendContent.Left + tb.Width() + lineTextGap + lineLengthMinimum
-                                legendContent.Right = util.Math.MaxInt(legendContent.Right, right)
-                                labelCount++</span>
-                        }
-                }
-
-                <span class="cov0" title="0">legend = legend.Grow(legendContent)
-                legend.Right = legendContent.Right + legendPadding.Right
-                legend.Bottom = legendContent.Bottom + legendPadding.Bottom
-
-                Draw.Box(r, legend, legendStyle)
-
-                legendStyle.GetTextOptions().WriteToRenderer(r)
-
-                ycursor := legendContent.Top
-                tx := legendContent.Left
-                legendCount := 0
-                var label string
-                for x := 0; x &lt; len(labels); x++ </span><span class="cov0" title="0">{
-                        label = labels[x]
-                        if len(label) &gt; 0 </span><span class="cov0" title="0">{
-                                if legendCount &gt; 0 </span><span class="cov0" title="0">{
-                                        ycursor += DefaultMinimumTickVerticalSpacing
-                                }</span>
-
-                                <span class="cov0" title="0">tb := r.MeasureText(label)
-
-                                ty := ycursor + tb.Height()
-                                r.Text(label, tx, ty)
-
-                                th2 := tb.Height() &gt;&gt; 1
-
-                                lx := tx + tb.Width() + lineTextGap
-                                ly := ty - th2
-                                lx2 := legendContent.Right - legendPadding.Right
-
-                                r.SetStrokeColor(lines[x].GetStrokeColor())
-                                r.SetStrokeWidth(lines[x].GetStrokeWidth())
-                                r.SetStrokeDashArray(lines[x].GetStrokeDashArray())
-
-                                r.MoveTo(lx, ly)
-                                r.LineTo(lx2, ly)
-                                r.Stroke()
-
-                                ycursor += tb.Height()
-                                legendCount++</span>
-                        }
-                }
-        }
-}
-</pre>
-		
-		<pre class="file" id="file35" style="display: none">package chart
-
-// LinearCoefficientProvider is a type that returns linear cofficients.
-type LinearCoefficientProvider interface {
-        Coefficients() (m, b, stdev, avg float64)
-}
-
-// LinearCoefficients returns a fixed linear coefficient pair.
-func LinearCoefficients(m, b float64) LinearCoefficientSet <span class="cov0" title="0">{
-        return LinearCoefficientSet{
-                M: m,
-                B: b,
-        }
-}</span>
-
-// NormalizedLinearCoefficients returns a fixed linear coefficient pair.
-func NormalizedLinearCoefficients(m, b, stdev, avg float64) LinearCoefficientSet <span class="cov0" title="0">{
-        return LinearCoefficientSet{
-                M:      m,
-                B:      b,
-                StdDev: stdev,
-                Avg:    avg,
-        }
-}</span>
-
-// LinearCoefficientSet is the m and b values for the linear equation in the form:
-// y = (m*x) + b
-type LinearCoefficientSet struct {
-        M      float64
-        B      float64
-        StdDev float64
-        Avg    float64
-}
-
-// Coefficients returns the coefficients.
-func (lcs LinearCoefficientSet) Coefficients() (m, b, stdev, avg float64) <span class="cov0" title="0">{
-        m = lcs.M
-        b = lcs.B
-        stdev = lcs.StdDev
-        avg = lcs.Avg
-        return
-}</span>
-</pre>
-		
-		<pre class="file" id="file36" style="display: none">package chart
-
-import (
-        "fmt"
-
-        "github.com/wcharczuk/go-chart/seq"
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// Interface Assertions.
-var (
-        _ Series                    = (*LinearRegressionSeries)(nil)
-        _ FirstValuesProvider       = (*LinearRegressionSeries)(nil)
-        _ LastValuesProvider        = (*LinearRegressionSeries)(nil)
-        _ LinearCoefficientProvider = (*LinearRegressionSeries)(nil)
-)
-
-// LinearRegressionSeries is a series that plots the n-nearest neighbors
-// linear regression for the values.
-type LinearRegressionSeries struct {
-        Name  string
-        Style Style
-        YAxis YAxisType
-
-        Limit       int
-        Offset      int
-        InnerSeries ValuesProvider
-
-        m       float64
-        b       float64
-        avgx    float64
-        stddevx float64
-}
-
-// Coefficients returns the linear coefficients for the series.
-func (lrs LinearRegressionSeries) Coefficients() (m, b, stdev, avg float64) <span class="cov0" title="0">{
-        if lrs.IsZero() </span><span class="cov0" title="0">{
-                lrs.computeCoefficients()
-        }</span>
-
-        <span class="cov0" title="0">m = lrs.m
-        b = lrs.b
-        stdev = lrs.stddevx
-        avg = lrs.avgx
-        return</span>
-}
-
-// GetName returns the name of the time series.
-func (lrs LinearRegressionSeries) GetName() string <span class="cov0" title="0">{
-        return lrs.Name
-}</span>
-
-// GetStyle returns the line style.
-func (lrs LinearRegressionSeries) GetStyle() Style <span class="cov0" title="0">{
-        return lrs.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (lrs LinearRegressionSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return lrs.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (lrs LinearRegressionSeries) Len() int <span class="cov8" title="1">{
-        return util.Math.MinInt(lrs.GetLimit(), lrs.InnerSeries.Len()-lrs.GetOffset())
-}</span>
-
-// GetLimit returns the window size.
-func (lrs LinearRegressionSeries) GetLimit() int <span class="cov8" title="1">{
-        if lrs.Limit == 0 </span><span class="cov8" title="1">{
-                return lrs.InnerSeries.Len()
-        }</span>
-        <span class="cov8" title="1">return lrs.Limit</span>
-}
-
-// GetEndIndex returns the effective limit end.
-func (lrs LinearRegressionSeries) GetEndIndex() int <span class="cov8" title="1">{
-        windowEnd := lrs.GetOffset() + lrs.GetLimit()
-        innerSeriesLastIndex := lrs.InnerSeries.Len() - 1
-        return util.Math.MinInt(windowEnd, innerSeriesLastIndex)
-}</span>
-
-// GetOffset returns the data offset.
-func (lrs LinearRegressionSeries) GetOffset() int <span class="cov8" title="1">{
-        if lrs.Offset == 0 </span><span class="cov8" title="1">{
-                return 0
-        }</span>
-        <span class="cov8" title="1">return lrs.Offset</span>
-}
-
-// GetValues gets a value at a given index.
-func (lrs *LinearRegressionSeries) GetValues(index int) (x, y float64) <span class="cov8" title="1">{
-        if lrs.InnerSeries == nil || lrs.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">if lrs.IsZero() </span><span class="cov8" title="1">{
-                lrs.computeCoefficients()
-        }</span>
-        <span class="cov8" title="1">offset := lrs.GetOffset()
-        effectiveIndex := util.Math.MinInt(index+offset, lrs.InnerSeries.Len())
-        x, y = lrs.InnerSeries.GetValues(effectiveIndex)
-        y = (lrs.m * lrs.normalize(x)) + lrs.b
-        return</span>
-}
-
-// GetFirstValues computes the first linear regression value.
-func (lrs *LinearRegressionSeries) GetFirstValues() (x, y float64) <span class="cov0" title="0">{
-        if lrs.InnerSeries == nil || lrs.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">if lrs.IsZero() </span><span class="cov0" title="0">{
-                lrs.computeCoefficients()
-        }</span>
-        <span class="cov0" title="0">x, y = lrs.InnerSeries.GetValues(0)
-        y = (lrs.m * lrs.normalize(x)) + lrs.b
-        return</span>
-}
-
-// GetLastValues computes the last linear regression value.
-func (lrs *LinearRegressionSeries) GetLastValues() (x, y float64) <span class="cov8" title="1">{
-        if lrs.InnerSeries == nil || lrs.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">if lrs.IsZero() </span><span class="cov0" title="0">{
-                lrs.computeCoefficients()
-        }</span>
-        <span class="cov8" title="1">endIndex := lrs.GetEndIndex()
-        x, y = lrs.InnerSeries.GetValues(endIndex)
-        y = (lrs.m * lrs.normalize(x)) + lrs.b
-        return</span>
-}
-
-// Render renders the series.
-func (lrs *LinearRegressionSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := lrs.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, lrs)
-}</span>
-
-// Validate validates the series.
-func (lrs *LinearRegressionSeries) Validate() error <span class="cov0" title="0">{
-        if lrs.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("linear regression series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-
-// IsZero returns if we've computed the coefficients or not.
-func (lrs *LinearRegressionSeries) IsZero() bool <span class="cov8" title="1">{
-        return lrs.m == 0 &amp;&amp; lrs.b == 0
-}</span>
-
-//
-// internal helpers
-//
-
-func (lrs *LinearRegressionSeries) normalize(xvalue float64) float64 <span class="cov8" title="1">{
-        return (xvalue - lrs.avgx) / lrs.stddevx
-}</span>
-
-// computeCoefficients computes the `m` and `b` terms in the linear formula given by `y = mx+b`.
-func (lrs *LinearRegressionSeries) computeCoefficients() <span class="cov8" title="1">{
-        startIndex := lrs.GetOffset()
-        endIndex := lrs.GetEndIndex()
-
-        p := float64(endIndex - startIndex)
-
-        xvalues := seq.NewBufferWithCapacity(lrs.Len())
-        for index := startIndex; index &lt; endIndex; index++ </span><span class="cov8" title="1">{
-                x, _ := lrs.InnerSeries.GetValues(index)
-                xvalues.Enqueue(x)
-        }</span>
-
-        <span class="cov8" title="1">lrs.avgx = seq.Seq{Provider: xvalues}.Average()
-        lrs.stddevx = seq.Seq{Provider: xvalues}.StdDev()
-
-        var sumx, sumy, sumxx, sumxy float64
-        for index := startIndex; index &lt; endIndex; index++ </span><span class="cov8" title="1">{
-                x, y := lrs.InnerSeries.GetValues(index)
-
-                x = lrs.normalize(x)
-
-                sumx += x
-                sumy += y
-                sumxx += x * x
-                sumxy += x * y
-        }</span>
-
-        <span class="cov8" title="1">lrs.m = (p*sumxy - sumx*sumy) / (p*sumxx - sumx*sumx)
-        lrs.b = (sumy / p) - (lrs.m * sumx / p)</span>
-}
-</pre>
-		
-		<pre class="file" id="file37" style="display: none">package chart
-
-import (
-        "fmt"
-)
-
-// Interface Assertions.
-var (
-        _ Series              = (*LinearSeries)(nil)
-        _ FirstValuesProvider = (*LinearSeries)(nil)
-        _ LastValuesProvider  = (*LinearSeries)(nil)
-)
-
-// LinearSeries is a series that plots a line in a given domain.
-type LinearSeries struct {
-        Name  string
-        Style Style
-        YAxis YAxisType
-
-        XValues     []float64
-        InnerSeries LinearCoefficientProvider
-
-        m     float64
-        b     float64
-        stdev float64
-        avg   float64
-}
-
-// GetName returns the name of the time series.
-func (ls LinearSeries) GetName() string <span class="cov0" title="0">{
-        return ls.Name
-}</span>
-
-// GetStyle returns the line style.
-func (ls LinearSeries) GetStyle() Style <span class="cov0" title="0">{
-        return ls.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (ls LinearSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return ls.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (ls LinearSeries) Len() int <span class="cov0" title="0">{
-        return len(ls.XValues)
-}</span>
-
-// GetEndIndex returns the effective limit end.
-func (ls LinearSeries) GetEndIndex() int <span class="cov0" title="0">{
-        return len(ls.XValues) - 1
-}</span>
-
-// GetValues gets a value at a given index.
-func (ls *LinearSeries) GetValues(index int) (x, y float64) <span class="cov0" title="0">{
-        if ls.InnerSeries == nil || len(ls.XValues) == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">if ls.IsZero() </span><span class="cov0" title="0">{
-                ls.computeCoefficients()
-        }</span>
-        <span class="cov0" title="0">x = ls.XValues[index]
-        y = (ls.m * ls.normalize(x)) + ls.b
-        return</span>
-}
-
-// GetFirstValues computes the first linear regression value.
-func (ls *LinearSeries) GetFirstValues() (x, y float64) <span class="cov0" title="0">{
-        if ls.InnerSeries == nil || len(ls.XValues) == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">if ls.IsZero() </span><span class="cov0" title="0">{
-                ls.computeCoefficients()
-        }</span>
-        <span class="cov0" title="0">x, y = ls.GetValues(0)
-        return</span>
-}
-
-// GetLastValues computes the last linear regression value.
-func (ls *LinearSeries) GetLastValues() (x, y float64) <span class="cov0" title="0">{
-        if ls.InnerSeries == nil || len(ls.XValues) == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">if ls.IsZero() </span><span class="cov0" title="0">{
-                ls.computeCoefficients()
-        }</span>
-        <span class="cov0" title="0">x, y = ls.GetValues(ls.GetEndIndex())
-        return</span>
-}
-
-// Render renders the series.
-func (ls *LinearSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        Draw.LineSeries(r, canvasBox, xrange, yrange, ls.Style.InheritFrom(defaults), ls)
-}</span>
-
-// Validate validates the series.
-func (ls LinearSeries) Validate() error <span class="cov0" title="0">{
-        if ls.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("linear regression series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-
-// IsZero returns if the linear series has computed coefficients or not.
-func (ls LinearSeries) IsZero() bool <span class="cov0" title="0">{
-        return ls.m == 0 &amp;&amp; ls.b == 0
-}</span>
-
-// computeCoefficients computes the `m` and `b` terms in the linear formula given by `y = mx+b`.
-func (ls *LinearSeries) computeCoefficients() <span class="cov0" title="0">{
-        ls.m, ls.b, ls.stdev, ls.avg = ls.InnerSeries.Coefficients()
-}</span>
-
-func (ls *LinearSeries) normalize(xvalue float64) float64 <span class="cov0" title="0">{
-        if ls.avg &gt; 0 &amp;&amp; ls.stdev &gt; 0 </span><span class="cov0" title="0">{
-                return (xvalue - ls.avg) / ls.stdev
-        }</span>
-        <span class="cov0" title="0">return xvalue</span>
-}
-</pre>
-		
-		<pre class="file" id="file38" style="display: none">package chart
-
-import "fmt"
-
-const (
-        // DefaultMACDPeriodPrimary is the long window.
-        DefaultMACDPeriodPrimary = 26
-        // DefaultMACDPeriodSecondary is the short window.
-        DefaultMACDPeriodSecondary = 12
-        // DefaultMACDSignalPeriod is the signal period to compute for the MACD.
-        DefaultMACDSignalPeriod = 9
-)
-
-// MACDSeries computes the difference between the MACD line and the MACD Signal line.
-// It is used in technical analysis and gives a lagging indicator of momentum.
-type MACDSeries struct {
-        Name        string
-        Style       Style
-        YAxis       YAxisType
-        InnerSeries ValuesProvider
-
-        PrimaryPeriod   int
-        SecondaryPeriod int
-        SignalPeriod    int
-
-        signal *MACDSignalSeries
-        macdl  *MACDLineSeries
-}
-
-// Validate validates the series.
-func (macd MACDSeries) Validate() error <span class="cov0" title="0">{
-        var err error
-        if macd.signal != nil </span><span class="cov0" title="0">{
-                err = macd.signal.Validate()
-        }</span>
-        <span class="cov0" title="0">if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-        <span class="cov0" title="0">if macd.macdl != nil </span><span class="cov0" title="0">{
-                err = macd.macdl.Validate()
-        }</span>
-        <span class="cov0" title="0">if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-
-// GetPeriods returns the primary and secondary periods.
-func (macd MACDSeries) GetPeriods() (w1, w2, sig int) <span class="cov8" title="1">{
-        if macd.PrimaryPeriod == 0 </span><span class="cov8" title="1">{
-                w1 = DefaultMACDPeriodPrimary
-        }</span> else<span class="cov0" title="0"> {
-                w1 = macd.PrimaryPeriod
-        }</span>
-        <span class="cov8" title="1">if macd.SecondaryPeriod == 0 </span><span class="cov8" title="1">{
-                w2 = DefaultMACDPeriodSecondary
-        }</span> else<span class="cov0" title="0"> {
-                w2 = macd.SecondaryPeriod
-        }</span>
-        <span class="cov8" title="1">if macd.SignalPeriod == 0 </span><span class="cov8" title="1">{
-                sig = DefaultMACDSignalPeriod
-        }</span> else<span class="cov0" title="0"> {
-                sig = macd.SignalPeriod
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// GetName returns the name of the time series.
-func (macd MACDSeries) GetName() string <span class="cov0" title="0">{
-        return macd.Name
-}</span>
-
-// GetStyle returns the line style.
-func (macd MACDSeries) GetStyle() Style <span class="cov0" title="0">{
-        return macd.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (macd MACDSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return macd.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (macd MACDSeries) Len() int <span class="cov8" title="1">{
-        if macd.InnerSeries == nil </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">return macd.InnerSeries.Len()</span>
-}
-
-// GetValues gets a value at a given index. For MACD it is the signal value.
-func (macd *MACDSeries) GetValues(index int) (x float64, y float64) <span class="cov8" title="1">{
-        if macd.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        <span class="cov8" title="1">if macd.signal == nil || macd.macdl == nil </span><span class="cov8" title="1">{
-                macd.ensureChildSeries()
-        }</span>
-
-        <span class="cov8" title="1">_, lv := macd.macdl.GetValues(index)
-        _, sv := macd.signal.GetValues(index)
-
-        x, _ = macd.InnerSeries.GetValues(index)
-        y = lv - sv
-
-        return</span>
-}
-
-func (macd *MACDSeries) ensureChildSeries() <span class="cov8" title="1">{
-        w1, w2, sig := macd.GetPeriods()
-
-        macd.signal = &amp;MACDSignalSeries{
-                InnerSeries:     macd.InnerSeries,
-                PrimaryPeriod:   w1,
-                SecondaryPeriod: w2,
-                SignalPeriod:    sig,
-        }
-
-        macd.macdl = &amp;MACDLineSeries{
-                InnerSeries:     macd.InnerSeries,
-                PrimaryPeriod:   w1,
-                SecondaryPeriod: w2,
-        }
-}</span>
-
-// MACDSignalSeries computes the EMA of the MACDLineSeries.
-type MACDSignalSeries struct {
-        Name        string
-        Style       Style
-        YAxis       YAxisType
-        InnerSeries ValuesProvider
-
-        PrimaryPeriod   int
-        SecondaryPeriod int
-        SignalPeriod    int
-
-        signal *EMASeries
-}
-
-// Validate validates the series.
-func (macds MACDSignalSeries) Validate() error <span class="cov0" title="0">{
-        if macds.signal != nil </span><span class="cov0" title="0">{
-                return macds.signal.Validate()
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-
-// GetPeriods returns the primary and secondary periods.
-func (macds MACDSignalSeries) GetPeriods() (w1, w2, sig int) <span class="cov8" title="1">{
-        if macds.PrimaryPeriod == 0 </span><span class="cov0" title="0">{
-                w1 = DefaultMACDPeriodPrimary
-        }</span> else<span class="cov8" title="1"> {
-                w1 = macds.PrimaryPeriod
-        }</span>
-        <span class="cov8" title="1">if macds.SecondaryPeriod == 0 </span><span class="cov0" title="0">{
-                w2 = DefaultMACDPeriodSecondary
-        }</span> else<span class="cov8" title="1"> {
-                w2 = macds.SecondaryPeriod
-        }</span>
-        <span class="cov8" title="1">if macds.SignalPeriod == 0 </span><span class="cov0" title="0">{
-                sig = DefaultMACDSignalPeriod
-        }</span> else<span class="cov8" title="1"> {
-                sig = macds.SignalPeriod
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// GetName returns the name of the time series.
-func (macds MACDSignalSeries) GetName() string <span class="cov0" title="0">{
-        return macds.Name
-}</span>
-
-// GetStyle returns the line style.
-func (macds MACDSignalSeries) GetStyle() Style <span class="cov0" title="0">{
-        return macds.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (macds MACDSignalSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return macds.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (macds *MACDSignalSeries) Len() int <span class="cov0" title="0">{
-        if macds.InnerSeries == nil </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov0" title="0">return macds.InnerSeries.Len()</span>
-}
-
-// GetValues gets a value at a given index. For MACD it is the signal value.
-func (macds *MACDSignalSeries) GetValues(index int) (x float64, y float64) <span class="cov8" title="1">{
-        if macds.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        <span class="cov8" title="1">if macds.signal == nil </span><span class="cov8" title="1">{
-                macds.ensureSignal()
-        }</span>
-        <span class="cov8" title="1">x, _ = macds.InnerSeries.GetValues(index)
-        _, y = macds.signal.GetValues(index)
-        return</span>
-}
-
-func (macds *MACDSignalSeries) ensureSignal() <span class="cov8" title="1">{
-        w1, w2, sig := macds.GetPeriods()
-
-        macds.signal = &amp;EMASeries{
-                InnerSeries: &amp;MACDLineSeries{
-                        InnerSeries:     macds.InnerSeries,
-                        PrimaryPeriod:   w1,
-                        SecondaryPeriod: w2,
-                },
-                Period: sig,
-        }
-}</span>
-
-// Render renders the series.
-func (macds *MACDSignalSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := macds.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, macds)
-}</span>
-
-// MACDLineSeries is a series that computes the inner ema1-ema2 value as a series.
-type MACDLineSeries struct {
-        Name        string
-        Style       Style
-        YAxis       YAxisType
-        InnerSeries ValuesProvider
-
-        PrimaryPeriod   int
-        SecondaryPeriod int
-
-        ema1 *EMASeries
-        ema2 *EMASeries
-
-        Sigma float64
-}
-
-// Validate validates the series.
-func (macdl MACDLineSeries) Validate() error <span class="cov0" title="0">{
-        var err error
-        if macdl.ema1 != nil </span><span class="cov0" title="0">{
-                err = macdl.ema1.Validate()
-        }</span>
-        <span class="cov0" title="0">if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-        <span class="cov0" title="0">if macdl.ema2 != nil </span><span class="cov0" title="0">{
-                err = macdl.ema2.Validate()
-        }</span>
-        <span class="cov0" title="0">if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-        <span class="cov0" title="0">if macdl.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("MACDLineSeries: must provide an inner series")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-
-// GetName returns the name of the time series.
-func (macdl MACDLineSeries) GetName() string <span class="cov0" title="0">{
-        return macdl.Name
-}</span>
-
-// GetStyle returns the line style.
-func (macdl MACDLineSeries) GetStyle() Style <span class="cov0" title="0">{
-        return macdl.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (macdl MACDLineSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return macdl.YAxis
-}</span>
-
-// GetPeriods returns the primary and secondary periods.
-func (macdl MACDLineSeries) GetPeriods() (w1, w2 int) <span class="cov8" title="1">{
-        if macdl.PrimaryPeriod == 0 </span><span class="cov0" title="0">{
-                w1 = DefaultMACDPeriodPrimary
-        }</span> else<span class="cov8" title="1"> {
-                w1 = macdl.PrimaryPeriod
-        }</span>
-        <span class="cov8" title="1">if macdl.SecondaryPeriod == 0 </span><span class="cov0" title="0">{
-                w2 = DefaultMACDPeriodSecondary
-        }</span> else<span class="cov8" title="1"> {
-                w2 = macdl.SecondaryPeriod
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// Len returns the number of elements in the series.
-func (macdl *MACDLineSeries) Len() int <span class="cov8" title="1">{
-        if macdl.InnerSeries == nil </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">return macdl.InnerSeries.Len()</span>
-}
-
-// GetValues gets a value at a given index. For MACD it is the signal value.
-func (macdl *MACDLineSeries) GetValues(index int) (x float64, y float64) <span class="cov8" title="1">{
-        if macdl.InnerSeries == nil </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">if macdl.ema1 == nil &amp;&amp; macdl.ema2 == nil </span><span class="cov8" title="1">{
-                macdl.ensureEMASeries()
-        }</span>
-
-        <span class="cov8" title="1">x, _ = macdl.InnerSeries.GetValues(index)
-
-        _, emav1 := macdl.ema1.GetValues(index)
-        _, emav2 := macdl.ema2.GetValues(index)
-
-        y = emav2 - emav1
-        return</span>
-}
-
-func (macdl *MACDLineSeries) ensureEMASeries() <span class="cov8" title="1">{
-        w1, w2 := macdl.GetPeriods()
-
-        macdl.ema1 = &amp;EMASeries{
-                InnerSeries: macdl.InnerSeries,
-                Period:      w1,
-        }
-        macdl.ema2 = &amp;EMASeries{
-                InnerSeries: macdl.InnerSeries,
-                Period:      w2,
-        }
-}</span>
-
-// Render renders the series.
-func (macdl *MACDLineSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := macdl.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, macdl)
-}</span>
-</pre>
-		
-		<pre class="file" id="file39" style="display: none">package matrix
-
-import (
-        "bytes"
-        "errors"
-        "fmt"
-        "math"
-)
-
-const (
-        // DefaultEpsilon represents the minimum precision for matrix math operations.
-        DefaultEpsilon = 0.000001
-)
-
-var (
-        // ErrDimensionMismatch is a typical error.
-        ErrDimensionMismatch = errors.New("dimension mismatch")
-
-        // ErrSingularValue is a typical error.
-        ErrSingularValue = errors.New("singular value")
-)
-
-// New returns a new matrix.
-func New(rows, cols int, values ...float64) *Matrix <span class="cov8" title="1">{
-        if len(values) == 0 </span><span class="cov8" title="1">{
-                return &amp;Matrix{
-                        stride:   cols,
-                        epsilon:  DefaultEpsilon,
-                        elements: make([]float64, rows*cols),
-                }
-        }</span>
-        <span class="cov8" title="1">elems := make([]float64, rows*cols)
-        copy(elems, values)
-        return &amp;Matrix{
-                stride:   cols,
-                epsilon:  DefaultEpsilon,
-                elements: elems,
-        }</span>
-}
-
-// Identity returns the identity matrix of a given order.
-func Identity(order int) *Matrix <span class="cov8" title="1">{
-        m := New(order, order)
-        for i := 0; i &lt; order; i++ </span><span class="cov8" title="1">{
-                m.Set(i, i, 1)
-        }</span>
-        <span class="cov8" title="1">return m</span>
-}
-
-// Zero returns a matrix of a given size zeroed.
-func Zero(rows, cols int) *Matrix <span class="cov8" title="1">{
-        return New(rows, cols)
-}</span>
-
-// Ones returns an matrix of ones.
-func Ones(rows, cols int) *Matrix <span class="cov8" title="1">{
-        ones := make([]float64, rows*cols)
-        for i := 0; i &lt; (rows * cols); i++ </span><span class="cov8" title="1">{
-                ones[i] = 1
-        }</span>
-
-        <span class="cov8" title="1">return &amp;Matrix{
-                stride:   cols,
-                epsilon:  DefaultEpsilon,
-                elements: ones,
-        }</span>
-}
-
-// Eye returns the eye matrix.
-func Eye(n int) *Matrix <span class="cov0" title="0">{
-        m := Zero(n, n)
-        for i := 0; i &lt; len(m.elements); i += n + 1 </span><span class="cov0" title="0">{
-                m.elements[i] = 1
-        }</span>
-        <span class="cov0" title="0">return m</span>
-}
-
-// NewFromArrays creates a matrix from a jagged array set.
-func NewFromArrays(a [][]float64) *Matrix <span class="cov8" title="1">{
-        rows := len(a)
-        if rows == 0 </span><span class="cov0" title="0">{
-                return nil
-        }</span>
-        <span class="cov8" title="1">cols := len(a[0])
-        m := New(rows, cols)
-        for row := 0; row &lt; rows; row++ </span><span class="cov8" title="1">{
-                for col := 0; col &lt; cols; col++ </span><span class="cov8" title="1">{
-                        m.Set(row, col, a[row][col])
-                }</span>
-        }
-        <span class="cov8" title="1">return m</span>
-}
-
-// Matrix represents a 2d dense array of floats.
-type Matrix struct {
-        epsilon  float64
-        elements []float64
-        stride   int
-}
-
-// String returns a string representation of the matrix.
-func (m *Matrix) String() string <span class="cov8" title="1">{
-        buffer := bytes.NewBuffer(nil)
-        rows, cols := m.Size()
-
-        for row := 0; row &lt; rows; row++ </span><span class="cov8" title="1">{
-                for col := 0; col &lt; cols; col++ </span><span class="cov8" title="1">{
-                        buffer.WriteString(f64s(m.Get(row, col)))
-                        buffer.WriteRune(' ')
-                }</span>
-                <span class="cov8" title="1">buffer.WriteRune('\n')</span>
-        }
-        <span class="cov8" title="1">return buffer.String()</span>
-}
-
-// Epsilon returns the maximum precision for math operations.
-func (m *Matrix) Epsilon() float64 <span class="cov8" title="1">{
-        return m.epsilon
-}</span>
-
-// WithEpsilon sets the epsilon on the matrix and returns a reference to the matrix.
-func (m *Matrix) WithEpsilon(epsilon float64) *Matrix <span class="cov8" title="1">{
-        m.epsilon = epsilon
-        return m
-}</span>
-
-// Each applies the action to each element of the matrix in
-// rows =&gt; cols order.
-func (m *Matrix) Each(action func(row, col int, value float64)) <span class="cov0" title="0">{
-        rows, cols := m.Size()
-        for row := 0; row &lt; rows; row++ </span><span class="cov0" title="0">{
-                for col := 0; col &lt; cols; col++ </span><span class="cov0" title="0">{
-                        action(row, col, m.Get(row, col))
-                }</span>
-        }
-}
-
-// Round rounds all the values in a matrix to it epsilon,
-// returning a reference to the original
-func (m *Matrix) Round() *Matrix <span class="cov8" title="1">{
-        rows, cols := m.Size()
-        for row := 0; row &lt; rows; row++ </span><span class="cov8" title="1">{
-                for col := 0; col &lt; cols; col++ </span><span class="cov8" title="1">{
-                        m.Set(row, col, roundToEpsilon(m.Get(row, col), m.epsilon))
-                }</span>
-        }
-        <span class="cov8" title="1">return m</span>
-}
-
-// Arrays returns the matrix as a two dimensional jagged array.
-func (m *Matrix) Arrays() [][]float64 <span class="cov8" title="1">{
-        rows, cols := m.Size()
-        a := make([][]float64, rows)
-
-        for row := 0; row &lt; rows; row++ </span><span class="cov8" title="1">{
-                a[row] = make([]float64, cols)
-
-                for col := 0; col &lt; cols; col++ </span><span class="cov8" title="1">{
-                        a[row][col] = m.Get(row, col)
-                }</span>
-        }
-        <span class="cov8" title="1">return a</span>
-}
-
-// Size returns the dimensions of the matrix.
-func (m *Matrix) Size() (rows, cols int) <span class="cov8" title="1">{
-        rows = len(m.elements) / m.stride
-        cols = m.stride
-        return
-}</span>
-
-// IsSquare returns if the row count is equal to the column count.
-func (m *Matrix) IsSquare() bool <span class="cov8" title="1">{
-        return m.stride == (len(m.elements) / m.stride)
-}</span>
-
-// IsSymmetric returns if the matrix is symmetric about its diagonal.
-func (m *Matrix) IsSymmetric() bool <span class="cov8" title="1">{
-        rows, cols := m.Size()
-
-        if rows != cols </span><span class="cov8" title="1">{
-                return false
-        }</span>
-
-        <span class="cov8" title="1">for i := 0; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                for j := 0; j &lt; i; j++ </span><span class="cov8" title="1">{
-                        if m.Get(i, j) != m.Get(j, i) </span><span class="cov8" title="1">{
-                                return false
-                        }</span>
-                }
-        }
-        <span class="cov8" title="1">return true</span>
-}
-
-// Get returns the element at the given row, col.
-func (m *Matrix) Get(row, col int) float64 <span class="cov8" title="1">{
-        index := (m.stride * row) + col
-        return m.elements[index]
-}</span>
-
-// Set sets a value.
-func (m *Matrix) Set(row, col int, val float64) <span class="cov8" title="1">{
-        index := (m.stride * row) + col
-        m.elements[index] = val
-}</span>
-
-// Col returns a column of the matrix as a vector.
-func (m *Matrix) Col(col int) Vector <span class="cov8" title="1">{
-        rows, _ := m.Size()
-        values := make([]float64, rows)
-        for row := 0; row &lt; rows; row++ </span><span class="cov8" title="1">{
-                values[row] = m.Get(row, col)
-        }</span>
-        <span class="cov8" title="1">return Vector(values)</span>
-}
-
-// Row returns a row of the matrix as a vector.
-func (m *Matrix) Row(row int) Vector <span class="cov8" title="1">{
-        _, cols := m.Size()
-        values := make([]float64, cols)
-        for col := 0; col &lt; cols; col++ </span><span class="cov8" title="1">{
-                values[col] = m.Get(row, col)
-        }</span>
-        <span class="cov8" title="1">return Vector(values)</span>
-}
-
-// SubMatrix returns a sub matrix from a given outer matrix.
-func (m *Matrix) SubMatrix(i, j, rows, cols int) *Matrix <span class="cov0" title="0">{
-        return &amp;Matrix{
-                elements: m.elements[i*m.stride+j : i*m.stride+j+(rows-1)*m.stride+cols],
-                stride:   m.stride,
-                epsilon:  m.epsilon,
-        }
-}</span>
-
-// ScaleRow applies a scale to an entire row.
-func (m *Matrix) ScaleRow(row int, scale float64) <span class="cov0" title="0">{
-        startIndex := row * m.stride
-        for i := startIndex; i &lt; m.stride; i++ </span><span class="cov0" title="0">{
-                m.elements[i] = m.elements[i] * scale
-        }</span>
-}
-
-func (m *Matrix) scaleAddRow(rd int, rs int, f float64) <span class="cov0" title="0">{
-        indexd := rd * m.stride
-        indexs := rs * m.stride
-        for col := 0; col &lt; m.stride; col++ </span><span class="cov0" title="0">{
-                m.elements[indexd] += f * m.elements[indexs]
-                indexd++
-                indexs++
-        }</span>
-}
-
-// SwapRows swaps a row in the matrix in place.
-func (m *Matrix) SwapRows(i, j int) <span class="cov8" title="1">{
-        var vi, vj float64
-        for col := 0; col &lt; m.stride; col++ </span><span class="cov8" title="1">{
-                vi = m.Get(i, col)
-                vj = m.Get(j, col)
-                m.Set(i, col, vj)
-                m.Set(j, col, vi)
-        }</span>
-}
-
-// Augment concatenates two matrices about the horizontal.
-func (m *Matrix) Augment(m2 *Matrix) (*Matrix, error) <span class="cov0" title="0">{
-        mr, mc := m.Size()
-        m2r, m2c := m2.Size()
-        if mr != m2r </span><span class="cov0" title="0">{
-                return nil, ErrDimensionMismatch
-        }</span>
-
-        <span class="cov0" title="0">m3 := Zero(mr, mc+m2c)
-        for row := 0; row &lt; mr; row++ </span><span class="cov0" title="0">{
-                for col := 0; col &lt; mc; col++ </span><span class="cov0" title="0">{
-                        m3.Set(row, col, m.Get(row, col))
-                }</span>
-                <span class="cov0" title="0">for col := 0; col &lt; m2c; col++ </span><span class="cov0" title="0">{
-                        m3.Set(row, mc+col, m2.Get(row, col))
-                }</span>
-        }
-        <span class="cov0" title="0">return m3, nil</span>
-}
-
-// Copy returns a duplicate of a given matrix.
-func (m *Matrix) Copy() *Matrix <span class="cov8" title="1">{
-        m2 := &amp;Matrix{stride: m.stride, epsilon: m.epsilon, elements: make([]float64, len(m.elements))}
-        copy(m2.elements, m.elements)
-        return m2
-}</span>
-
-// DiagonalVector returns a vector from the diagonal of a matrix.
-func (m *Matrix) DiagonalVector() Vector <span class="cov8" title="1">{
-        rows, cols := m.Size()
-        rank := minInt(rows, cols)
-        values := make([]float64, rank)
-
-        for index := 0; index &lt; rank; index++ </span><span class="cov8" title="1">{
-                values[index] = m.Get(index, index)
-        }</span>
-        <span class="cov8" title="1">return Vector(values)</span>
-}
-
-// Diagonal returns a matrix from the diagonal of a matrix.
-func (m *Matrix) Diagonal() *Matrix <span class="cov8" title="1">{
-        rows, cols := m.Size()
-        rank := minInt(rows, cols)
-        m2 := New(rank, rank)
-
-        for index := 0; index &lt; rank; index++ </span><span class="cov8" title="1">{
-                m2.Set(index, index, m.Get(index, index))
-        }</span>
-        <span class="cov8" title="1">return m2</span>
-}
-
-// Equals returns if a matrix equals another matrix.
-func (m *Matrix) Equals(other *Matrix) bool <span class="cov8" title="1">{
-        if other == nil &amp;&amp; m != nil </span><span class="cov8" title="1">{
-                return false
-        }</span> else<span class="cov8" title="1"> if other == nil </span><span class="cov8" title="1">{
-                return true
-        }</span>
-
-        <span class="cov8" title="1">if m.stride != other.stride </span><span class="cov8" title="1">{
-                return false
-        }</span>
-
-        <span class="cov8" title="1">msize := len(m.elements)
-        m2size := len(other.elements)
-
-        if msize != m2size </span><span class="cov0" title="0">{
-                return false
-        }</span>
-
-        <span class="cov8" title="1">for i := 0; i &lt; msize; i++ </span><span class="cov8" title="1">{
-                if m.elements[i] != other.elements[i] </span><span class="cov8" title="1">{
-                        return false
-                }</span>
-        }
-        <span class="cov8" title="1">return true</span>
-}
-
-// L returns the matrix with zeros below the diagonal.
-func (m *Matrix) L() *Matrix <span class="cov8" title="1">{
-        rows, cols := m.Size()
-        m2 := New(rows, cols)
-        for row := 0; row &lt; rows; row++ </span><span class="cov8" title="1">{
-                for col := row; col &lt; cols; col++ </span><span class="cov8" title="1">{
-                        m2.Set(row, col, m.Get(row, col))
-                }</span>
-        }
-        <span class="cov8" title="1">return m2</span>
-}
-
-// U returns the matrix with zeros above the diagonal.
-// Does not include the diagonal.
-func (m *Matrix) U() *Matrix <span class="cov8" title="1">{
-        rows, cols := m.Size()
-        m2 := New(rows, cols)
-        for row := 0; row &lt; rows; row++ </span><span class="cov8" title="1">{
-                for col := 0; col &lt; row &amp;&amp; col &lt; cols; col++ </span><span class="cov8" title="1">{
-                        m2.Set(row, col, m.Get(row, col))
-                }</span>
-        }
-        <span class="cov8" title="1">return m2</span>
-}
-
-// math operations
-
-// Multiply multiplies two matrices.
-func (m *Matrix) Multiply(m2 *Matrix) (m3 *Matrix, err error) <span class="cov8" title="1">{
-        if m.stride*m2.stride != len(m2.elements) </span><span class="cov0" title="0">{
-                return nil, ErrDimensionMismatch
-        }</span>
-
-        <span class="cov8" title="1">m3 = &amp;Matrix{epsilon: m.epsilon, stride: m2.stride, elements: make([]float64, (len(m.elements)/m.stride)*m2.stride)}
-        for m1c0, m3x := 0, 0; m1c0 &lt; len(m.elements); m1c0 += m.stride </span><span class="cov8" title="1">{
-                for m2r0 := 0; m2r0 &lt; m2.stride; m2r0++ </span><span class="cov8" title="1">{
-                        for m1x, m2x := m1c0, m2r0; m2x &lt; len(m2.elements); m2x += m2.stride </span><span class="cov8" title="1">{
-                                m3.elements[m3x] += m.elements[m1x] * m2.elements[m2x]
-                                m1x++
-                        }</span>
-                        <span class="cov8" title="1">m3x++</span>
-                }
-        }
-        <span class="cov8" title="1">return</span>
-}
-
-// Pivotize does something i'm not sure what.
-func (m *Matrix) Pivotize() *Matrix <span class="cov8" title="1">{
-        pv := make([]int, m.stride)
-
-        for i := range pv </span><span class="cov8" title="1">{
-                pv[i] = i
-        }</span>
-
-        <span class="cov8" title="1">for j, dx := 0, 0; j &lt; m.stride; j++ </span><span class="cov8" title="1">{
-                row := j
-                max := m.elements[dx]
-                for i, ixcj := j, dx; i &lt; m.stride; i++ </span><span class="cov8" title="1">{
-                        if m.elements[ixcj] &gt; max </span><span class="cov8" title="1">{
-                                max = m.elements[ixcj]
-                                row = i
-                        }</span>
-                        <span class="cov8" title="1">ixcj += m.stride</span>
-                }
-                <span class="cov8" title="1">if j != row </span><span class="cov8" title="1">{
-                        pv[row], pv[j] = pv[j], pv[row]
-                }</span>
-                <span class="cov8" title="1">dx += m.stride + 1</span>
-        }
-        <span class="cov8" title="1">p := Zero(m.stride, m.stride)
-        for r, c := range pv </span><span class="cov8" title="1">{
-                p.elements[r*m.stride+c] = 1
-        }</span>
-        <span class="cov8" title="1">return p</span>
-}
-
-// Times returns the product of a matrix and another.
-func (m *Matrix) Times(m2 *Matrix) (*Matrix, error) <span class="cov8" title="1">{
-        mr, mc := m.Size()
-        m2r, m2c := m2.Size()
-
-        if mc != m2r </span><span class="cov0" title="0">{
-                return nil, fmt.Errorf("cannot multiply (%dx%d) and (%dx%d)", mr, mc, m2r, m2c)
-                //return nil, ErrDimensionMismatch
-        }</span>
-
-        <span class="cov8" title="1">c := Zero(mr, m2c)
-
-        for i := 0; i &lt; mr; i++ </span><span class="cov8" title="1">{
-                sums := c.elements[i*c.stride : (i+1)*c.stride]
-                for k, a := range m.elements[i*m.stride : i*m.stride+m.stride] </span><span class="cov8" title="1">{
-                        for j, b := range m2.elements[k*m2.stride : k*m2.stride+m2.stride] </span><span class="cov8" title="1">{
-                                sums[j] += a * b
-                        }</span>
-                }
-        }
-
-        <span class="cov8" title="1">return c, nil</span>
-}
-
-// Decompositions
-
-// LU performs the LU decomposition.
-func (m *Matrix) LU() (l, u, p *Matrix) <span class="cov8" title="1">{
-        l = Zero(m.stride, m.stride)
-        u = Zero(m.stride, m.stride)
-        p = m.Pivotize()
-        m, _ = p.Multiply(m)
-        for j, jxc0 := 0, 0; j &lt; m.stride; j++ </span><span class="cov8" title="1">{
-                l.elements[jxc0+j] = 1
-                for i, ixc0 := 0, 0; ixc0 &lt;= jxc0; i++ </span><span class="cov8" title="1">{
-                        sum := 0.
-                        for k, kxcj := 0, j; k &lt; i; k++ </span><span class="cov8" title="1">{
-                                sum += u.elements[kxcj] * l.elements[ixc0+k]
-                                kxcj += m.stride
-                        }</span>
-                        <span class="cov8" title="1">u.elements[ixc0+j] = m.elements[ixc0+j] - sum
-                        ixc0 += m.stride</span>
-                }
-                <span class="cov8" title="1">for ixc0 := jxc0; ixc0 &lt; len(m.elements); ixc0 += m.stride </span><span class="cov8" title="1">{
-                        sum := 0.
-                        for k, kxcj := 0, j; k &lt; j; k++ </span><span class="cov8" title="1">{
-                                sum += u.elements[kxcj] * l.elements[ixc0+k]
-                                kxcj += m.stride
-                        }</span>
-                        <span class="cov8" title="1">l.elements[ixc0+j] = (m.elements[ixc0+j] - sum) / u.elements[jxc0+j]</span>
-                }
-                <span class="cov8" title="1">jxc0 += m.stride</span>
-        }
-        <span class="cov8" title="1">return</span>
-}
-
-// QR performs the qr decomposition.
-func (m *Matrix) QR() (q, r *Matrix) <span class="cov8" title="1">{
-        defer func() </span><span class="cov8" title="1">{
-                q = q.Round()
-                r = r.Round()
-        }</span>()
-
-        <span class="cov8" title="1">rows, cols := m.Size()
-        qr := m.Copy()
-        q = New(rows, cols)
-        r = New(rows, cols)
-
-        var i, j, k int
-        var norm, s float64
-
-        for k = 0; k &lt; cols; k++ </span><span class="cov8" title="1">{
-                norm = 0
-                for i = k; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                        norm = math.Hypot(norm, qr.Get(i, k))
-                }</span>
-
-                <span class="cov8" title="1">if norm != 0 </span><span class="cov8" title="1">{
-                        if qr.Get(k, k) &lt; 0 </span><span class="cov8" title="1">{
-                                norm = -norm
-                        }</span>
-
-                        <span class="cov8" title="1">for i = k; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                                qr.Set(i, k, qr.Get(i, k)/norm)
-                        }</span>
-                        <span class="cov8" title="1">qr.Set(k, k, qr.Get(k, k)+1.0)
-
-                        for j = k + 1; j &lt; cols; j++ </span><span class="cov8" title="1">{
-                                s = 0
-                                for i = k; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                                        s += qr.Get(i, k) * qr.Get(i, j)
-                                }</span>
-                                <span class="cov8" title="1">s = -s / qr.Get(k, k)
-                                for i = k; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                                        qr.Set(i, j, qr.Get(i, j)+s*qr.Get(i, k))
-
-                                        if i &lt; j </span><span class="cov8" title="1">{
-                                                r.Set(i, j, qr.Get(i, j))
-                                        }</span>
-                                }
-
-                        }
-                }
-
-                <span class="cov8" title="1">r.Set(k, k, -norm)</span>
-
-        }
-
-        //Q Matrix:
-        <span class="cov8" title="1">i, j, k = 0, 0, 0
-
-        for k = cols - 1; k &gt;= 0; k-- </span><span class="cov8" title="1">{
-                q.Set(k, k, 1.0)
-                for j = k; j &lt; cols; j++ </span><span class="cov8" title="1">{
-                        if qr.Get(k, k) != 0 </span><span class="cov8" title="1">{
-                                s = 0
-                                for i = k; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                                        s += qr.Get(i, k) * q.Get(i, j)
-                                }</span>
-                                <span class="cov8" title="1">s = -s / qr.Get(k, k)
-                                for i = k; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                                        q.Set(i, j, q.Get(i, j)+s*qr.Get(i, k))
-                                }</span>
-                        }
-                }
-        }
-
-        <span class="cov8" title="1">return</span>
-}
-
-// Transpose flips a matrix about its diagonal, returning a new copy.
-func (m *Matrix) Transpose() *Matrix <span class="cov8" title="1">{
-        rows, cols := m.Size()
-        m2 := Zero(cols, rows)
-        for i := 0; i &lt; rows; i++ </span><span class="cov8" title="1">{
-                for j := 0; j &lt; cols; j++ </span><span class="cov8" title="1">{
-                        m2.Set(j, i, m.Get(i, j))
-                }</span>
-        }
-        <span class="cov8" title="1">return m2</span>
-}
-
-// Inverse returns a matrix such that M*I==1.
-func (m *Matrix) Inverse() (*Matrix, error) <span class="cov0" title="0">{
-        if !m.IsSymmetric() </span><span class="cov0" title="0">{
-                return nil, ErrDimensionMismatch
-        }</span>
-
-        <span class="cov0" title="0">rows, cols := m.Size()
-
-        aug, _ := m.Augment(Eye(rows))
-        for i := 0; i &lt; rows; i++ </span><span class="cov0" title="0">{
-                j := i
-                for k := i; k &lt; rows; k++ </span><span class="cov0" title="0">{
-                        if math.Abs(aug.Get(k, i)) &gt; math.Abs(aug.Get(j, i)) </span><span class="cov0" title="0">{
-                                j = k
-                        }</span>
-                }
-                <span class="cov0" title="0">if j != i </span><span class="cov0" title="0">{
-                        aug.SwapRows(i, j)
-                }</span>
-                <span class="cov0" title="0">if aug.Get(i, i) == 0 </span><span class="cov0" title="0">{
-                        return nil, ErrSingularValue
-                }</span>
-                <span class="cov0" title="0">aug.ScaleRow(i, 1.0/aug.Get(i, i))
-                for k := 0; k &lt; rows; k++ </span><span class="cov0" title="0">{
-                        if k == i </span><span class="cov0" title="0">{
-                                continue</span>
-                        }
-                        <span class="cov0" title="0">aug.scaleAddRow(k, i, -aug.Get(k, i))</span>
-                }
-        }
-        <span class="cov0" title="0">return aug.SubMatrix(0, cols, rows, cols), nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file40" style="display: none">package matrix
-
-import "errors"
-
-var (
-        // ErrPolyRegArraysSameLength is a common error.
-        ErrPolyRegArraysSameLength = errors.New("polynomial array inputs must be the same length")
-)
-
-// Poly returns the polynomial regress of a given degree over the given values.
-func Poly(xvalues, yvalues []float64, degree int) ([]float64, error) <span class="cov8" title="1">{
-        if len(xvalues) != len(yvalues) </span><span class="cov0" title="0">{
-                return nil, ErrPolyRegArraysSameLength
-        }</span>
-
-        <span class="cov8" title="1">m := len(yvalues)
-        n := degree + 1
-        y := New(m, 1, yvalues...)
-        x := Zero(m, n)
-
-        for i := 0; i &lt; m; i++ </span><span class="cov8" title="1">{
-                ip := float64(1)
-                for j := 0; j &lt; n; j++ </span><span class="cov8" title="1">{
-                        x.Set(i, j, ip)
-                        ip *= xvalues[i]
-                }</span>
-        }
-
-        <span class="cov8" title="1">q, r := x.QR()
-        qty, err := q.Transpose().Times(y)
-        if err != nil </span><span class="cov0" title="0">{
-                return nil, err
-        }</span>
-
-        <span class="cov8" title="1">c := make([]float64, n)
-        for i := n - 1; i &gt;= 0; i-- </span><span class="cov8" title="1">{
-                c[i] = qty.Get(i, 0)
-                for j := i + 1; j &lt; n; j++ </span><span class="cov8" title="1">{
-                        c[i] -= c[j] * r.Get(i, j)
-                }</span>
-                <span class="cov8" title="1">c[i] /= r.Get(i, i)</span>
-        }
-
-        <span class="cov8" title="1">return c, nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file41" style="display: none">package matrix
-
-import (
-        "math"
-        "strconv"
-)
-
-func minInt(values ...int) int <span class="cov8" title="1">{
-        min := math.MaxInt32
-
-        for x := 0; x &lt; len(values); x++ </span><span class="cov8" title="1">{
-                if values[x] &lt; min </span><span class="cov8" title="1">{
-                        min = values[x]
-                }</span>
-        }
-        <span class="cov8" title="1">return min</span>
-}
-
-func maxInt(values ...int) int <span class="cov0" title="0">{
-        max := math.MinInt32
-
-        for x := 0; x &lt; len(values); x++ </span><span class="cov0" title="0">{
-                if values[x] &gt; max </span><span class="cov0" title="0">{
-                        max = values[x]
-                }</span>
-        }
-        <span class="cov0" title="0">return max</span>
-}
-
-func f64s(v float64) string <span class="cov8" title="1">{
-        return strconv.FormatFloat(v, 'f', -1, 64)
-}</span>
-
-func roundToEpsilon(value, epsilon float64) float64 <span class="cov8" title="1">{
-        return math.Nextafter(value, value)
-}</span>
-</pre>
-		
-		<pre class="file" id="file42" style="display: none">package matrix
-
-// Vector is just an array of values.
-type Vector []float64
-
-// DotProduct returns the dot product of two vectors.
-func (v Vector) DotProduct(v2 Vector) (result float64, err error) <span class="cov0" title="0">{
-        if len(v) != len(v2) </span><span class="cov0" title="0">{
-                err = ErrDimensionMismatch
-                return
-        }</span>
-
-        <span class="cov0" title="0">for i := 0; i &lt; len(v); i++ </span><span class="cov0" title="0">{
-                result = result + (v[i] * v2[i])
-        }</span>
-        <span class="cov0" title="0">return</span>
-}
-</pre>
-		
-		<pre class="file" id="file43" style="display: none">package chart
-
-import (
-        "fmt"
-        "math"
-)
-
-// MinSeries draws a horizontal line at the minimum value of the inner series.
-type MinSeries struct {
-        Name        string
-        Style       Style
-        YAxis       YAxisType
-        InnerSeries ValuesProvider
-
-        minValue *float64
-}
-
-// GetName returns the name of the time series.
-func (ms MinSeries) GetName() string <span class="cov0" title="0">{
-        return ms.Name
-}</span>
-
-// GetStyle returns the line style.
-func (ms MinSeries) GetStyle() Style <span class="cov0" title="0">{
-        return ms.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (ms MinSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return ms.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (ms MinSeries) Len() int <span class="cov0" title="0">{
-        return ms.InnerSeries.Len()
-}</span>
-
-// GetValues gets a value at a given index.
-func (ms *MinSeries) GetValues(index int) (x, y float64) <span class="cov0" title="0">{
-        ms.ensureMinValue()
-        x, _ = ms.InnerSeries.GetValues(index)
-        y = *ms.minValue
-        return
-}</span>
-
-// Render renders the series.
-func (ms *MinSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := ms.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, ms)
-}</span>
-
-func (ms *MinSeries) ensureMinValue() <span class="cov0" title="0">{
-        if ms.minValue == nil </span><span class="cov0" title="0">{
-                minValue := math.MaxFloat64
-                var y float64
-                for x := 0; x &lt; ms.InnerSeries.Len(); x++ </span><span class="cov0" title="0">{
-                        _, y = ms.InnerSeries.GetValues(x)
-                        if y &lt; minValue </span><span class="cov0" title="0">{
-                                minValue = y
-                        }</span>
-                }
-                <span class="cov0" title="0">ms.minValue = &amp;minValue</span>
-        }
-}
-
-// Validate validates the series.
-func (ms *MinSeries) Validate() error <span class="cov0" title="0">{
-        if ms.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("min series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-
-// MaxSeries draws a horizontal line at the maximum value of the inner series.
-type MaxSeries struct {
-        Name        string
-        Style       Style
-        YAxis       YAxisType
-        InnerSeries ValuesProvider
-
-        maxValue *float64
-}
-
-// GetName returns the name of the time series.
-func (ms MaxSeries) GetName() string <span class="cov0" title="0">{
-        return ms.Name
-}</span>
-
-// GetStyle returns the line style.
-func (ms MaxSeries) GetStyle() Style <span class="cov0" title="0">{
-        return ms.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (ms MaxSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return ms.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (ms MaxSeries) Len() int <span class="cov0" title="0">{
-        return ms.InnerSeries.Len()
-}</span>
-
-// GetValues gets a value at a given index.
-func (ms *MaxSeries) GetValues(index int) (x, y float64) <span class="cov0" title="0">{
-        ms.ensureMaxValue()
-        x, _ = ms.InnerSeries.GetValues(index)
-        y = *ms.maxValue
-        return
-}</span>
-
-// Render renders the series.
-func (ms *MaxSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := ms.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, ms)
-}</span>
-
-func (ms *MaxSeries) ensureMaxValue() <span class="cov0" title="0">{
-        if ms.maxValue == nil </span><span class="cov0" title="0">{
-                maxValue := -math.MaxFloat64
-                var y float64
-                for x := 0; x &lt; ms.InnerSeries.Len(); x++ </span><span class="cov0" title="0">{
-                        _, y = ms.InnerSeries.GetValues(x)
-                        if y &gt; maxValue </span><span class="cov0" title="0">{
-                                maxValue = y
-                        }</span>
-                }
-                <span class="cov0" title="0">ms.maxValue = &amp;maxValue</span>
-        }
-}
-
-// Validate validates the series.
-func (ms *MaxSeries) Validate() error <span class="cov0" title="0">{
-        if ms.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("max series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file44" style="display: none">package chart
-
-import (
-        "errors"
-        "fmt"
-        "io"
-        "math"
-
-        "github.com/golang/freetype/truetype"
-        "github.com/wcharczuk/go-chart/util"
-)
-
-const (
-        _pi  = math.Pi
-        _pi2 = math.Pi / 2.0
-        _pi4 = math.Pi / 4.0
-)
-
-// PieChart is a chart that draws sections of a circle based on percentages.
-type PieChart struct {
-        Title      string
-        TitleStyle Style
-
-        ColorPalette ColorPalette
-
-        Width  int
-        Height int
-        DPI    float64
-
-        Background Style
-        Canvas     Style
-        SliceStyle Style
-
-        Font        *truetype.Font
-        defaultFont *truetype.Font
-
-        Values   []Value
-        Elements []Renderable
-}
-
-// GetDPI returns the dpi for the chart.
-func (pc PieChart) GetDPI(defaults ...float64) float64 <span class="cov8" title="1">{
-        if pc.DPI == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return DefaultDPI</span>
-        }
-        <span class="cov0" title="0">return pc.DPI</span>
-}
-
-// GetFont returns the text font.
-func (pc PieChart) GetFont() *truetype.Font <span class="cov8" title="1">{
-        if pc.Font == nil </span><span class="cov8" title="1">{
-                return pc.defaultFont
-        }</span>
-        <span class="cov0" title="0">return pc.Font</span>
-}
-
-// GetWidth returns the chart width or the default value.
-func (pc PieChart) GetWidth() int <span class="cov8" title="1">{
-        if pc.Width == 0 </span><span class="cov8" title="1">{
-                return DefaultChartWidth
-        }</span>
-        <span class="cov0" title="0">return pc.Width</span>
-}
-
-// GetHeight returns the chart height or the default value.
-func (pc PieChart) GetHeight() int <span class="cov8" title="1">{
-        if pc.Height == 0 </span><span class="cov8" title="1">{
-                return DefaultChartWidth
-        }</span>
-        <span class="cov0" title="0">return pc.Height</span>
-}
-
-// Render renders the chart with the given renderer to the given io.Writer.
-func (pc PieChart) Render(rp RendererProvider, w io.Writer) error <span class="cov8" title="1">{
-        if len(pc.Values) == 0 </span><span class="cov0" title="0">{
-                return errors.New("please provide at least one value")
-        }</span>
-
-        <span class="cov8" title="1">r, err := rp(pc.GetWidth(), pc.GetHeight())
-        if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-
-        <span class="cov8" title="1">if pc.Font == nil </span><span class="cov8" title="1">{
-                defaultFont, err := GetDefaultFont()
-                if err != nil </span><span class="cov0" title="0">{
-                        return err
-                }</span>
-                <span class="cov8" title="1">pc.defaultFont = defaultFont</span>
-        }
-        <span class="cov8" title="1">r.SetDPI(pc.GetDPI(DefaultDPI))
-
-        canvasBox := pc.getDefaultCanvasBox()
-        canvasBox = pc.getCircleAdjustedCanvasBox(canvasBox)
-
-        pc.drawBackground(r)
-        pc.drawCanvas(r, canvasBox)
-
-        finalValues, err := pc.finalizeValues(pc.Values)
-        if err != nil </span><span class="cov8" title="1">{
-                return err
-        }</span>
-        <span class="cov8" title="1">pc.drawSlices(r, canvasBox, finalValues)
-        pc.drawTitle(r)
-        for _, a := range pc.Elements </span><span class="cov0" title="0">{
-                a(r, canvasBox, pc.styleDefaultsElements())
-        }</span>
-
-        <span class="cov8" title="1">return r.Save(w)</span>
-}
-
-func (pc PieChart) drawBackground(r Renderer) <span class="cov8" title="1">{
-        Draw.Box(r, Box{
-                Right:  pc.GetWidth(),
-                Bottom: pc.GetHeight(),
-        }, pc.getBackgroundStyle())
-}</span>
-
-func (pc PieChart) drawCanvas(r Renderer, canvasBox Box) <span class="cov8" title="1">{
-        Draw.Box(r, canvasBox, pc.getCanvasStyle())
-}</span>
-
-func (pc PieChart) drawTitle(r Renderer) <span class="cov8" title="1">{
-        if len(pc.Title) &gt; 0 &amp;&amp; pc.TitleStyle.Show </span><span class="cov0" title="0">{
-                Draw.TextWithin(r, pc.Title, pc.Box(), pc.styleDefaultsTitle())
-        }</span>
-}
-
-func (pc PieChart) drawSlices(r Renderer, canvasBox Box, values []Value) <span class="cov8" title="1">{
-        cx, cy := canvasBox.Center()
-        diameter := util.Math.MinInt(canvasBox.Width(), canvasBox.Height())
-        radius := float64(diameter &gt;&gt; 1)
-        labelRadius := (radius * 2.0) / 3.0
-
-        // draw the pie slices
-        var rads, delta, delta2, total float64
-        var lx, ly int
-
-        if len(values) == 1 </span><span class="cov0" title="0">{
-                pc.stylePieChartValue(0).WriteToRenderer(r)
-                r.MoveTo(cx, cy)
-                r.Circle(radius, cx, cy)
-        }</span> else<span class="cov8" title="1"> {
-                for index, v := range values </span><span class="cov8" title="1">{
-                        v.Style.InheritFrom(pc.stylePieChartValue(index)).WriteToRenderer(r)
-
-                        r.MoveTo(cx, cy)
-                        rads = util.Math.PercentToRadians(total)
-                        delta = util.Math.PercentToRadians(v.Value)
-
-                        r.ArcTo(cx, cy, radius, radius, rads, delta)
-
-                        r.LineTo(cx, cy)
-                        r.Close()
-                        r.FillStroke()
-                        total = total + v.Value
-                }</span>
-        }
-
-        // draw the labels
-        <span class="cov8" title="1">total = 0
-        for index, v := range values </span><span class="cov8" title="1">{
-                v.Style.InheritFrom(pc.stylePieChartValue(index)).WriteToRenderer(r)
-                if len(v.Label) &gt; 0 </span><span class="cov8" title="1">{
-                        delta2 = util.Math.PercentToRadians(total + (v.Value / 2.0))
-                        delta2 = util.Math.RadianAdd(delta2, _pi2)
-                        lx, ly = util.Math.CirclePoint(cx, cy, labelRadius, delta2)
-
-                        tb := r.MeasureText(v.Label)
-                        lx = lx - (tb.Width() &gt;&gt; 1)
-                        ly = ly + (tb.Height() &gt;&gt; 1)
-
-                        if lx &lt; 0 </span><span class="cov0" title="0">{
-                                lx = 0
-                        }</span>
-                        <span class="cov8" title="1">if ly &lt; 0 </span><span class="cov0" title="0">{
-                                lx = 0
-                        }</span>
-
-                        <span class="cov8" title="1">r.Text(v.Label, lx, ly)</span>
-                }
-                <span class="cov8" title="1">total = total + v.Value</span>
-        }
-}
-
-func (pc PieChart) finalizeValues(values []Value) ([]Value, error) <span class="cov8" title="1">{
-        finalValues := Values(values).Normalize()
-        if len(finalValues) == 0 </span><span class="cov8" title="1">{
-                return nil, fmt.Errorf("pie chart must contain at least (1) non-zero value")
-        }</span>
-        <span class="cov8" title="1">return finalValues, nil</span>
-}
-
-func (pc PieChart) getDefaultCanvasBox() Box <span class="cov8" title="1">{
-        return pc.Box()
-}</span>
-
-func (pc PieChart) getCircleAdjustedCanvasBox(canvasBox Box) Box <span class="cov8" title="1">{
-        circleDiameter := util.Math.MinInt(canvasBox.Width(), canvasBox.Height())
-
-        square := Box{
-                Right:  circleDiameter,
-                Bottom: circleDiameter,
-        }
-
-        return canvasBox.Fit(square)
-}</span>
-
-func (pc PieChart) getBackgroundStyle() Style <span class="cov8" title="1">{
-        return pc.Background.InheritFrom(pc.styleDefaultsBackground())
-}</span>
-
-func (pc PieChart) getCanvasStyle() Style <span class="cov8" title="1">{
-        return pc.Canvas.InheritFrom(pc.styleDefaultsCanvas())
-}</span>
-
-func (pc PieChart) styleDefaultsCanvas() Style <span class="cov8" title="1">{
-        return Style{
-                FillColor:   pc.GetColorPalette().CanvasColor(),
-                StrokeColor: pc.GetColorPalette().CanvasStrokeColor(),
-                StrokeWidth: DefaultStrokeWidth,
-        }
-}</span>
-
-func (pc PieChart) styleDefaultsPieChartValue() Style <span class="cov0" title="0">{
-        return Style{
-                StrokeColor: pc.GetColorPalette().TextColor(),
-                StrokeWidth: 5.0,
-                FillColor:   pc.GetColorPalette().TextColor(),
-        }
-}</span>
-
-func (pc PieChart) stylePieChartValue(index int) Style <span class="cov8" title="1">{
-        return pc.SliceStyle.InheritFrom(Style{
-                StrokeColor: ColorWhite,
-                StrokeWidth: 5.0,
-                FillColor:   pc.GetColorPalette().GetSeriesColor(index),
-                FontSize:    pc.getScaledFontSize(),
-                FontColor:   pc.GetColorPalette().TextColor(),
-                Font:        pc.GetFont(),
-        })
-}</span>
-
-func (pc PieChart) getScaledFontSize() float64 <span class="cov8" title="1">{
-        effectiveDimension := util.Math.MinInt(pc.GetWidth(), pc.GetHeight())
-        if effectiveDimension &gt;= 2048 </span><span class="cov0" title="0">{
-                return 48.0
-        }</span> else<span class="cov8" title="1"> if effectiveDimension &gt;= 1024 </span><span class="cov8" title="1">{
-                return 24.0
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt; 512 </span><span class="cov0" title="0">{
-                return 18.0
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt; 256 </span><span class="cov0" title="0">{
-                return 12.0
-        }</span>
-        <span class="cov0" title="0">return 10.0</span>
-}
-
-func (pc PieChart) styleDefaultsBackground() Style <span class="cov8" title="1">{
-        return Style{
-                FillColor:   pc.GetColorPalette().BackgroundColor(),
-                StrokeColor: pc.GetColorPalette().BackgroundStrokeColor(),
-                StrokeWidth: DefaultStrokeWidth,
-        }
-}</span>
-
-func (pc PieChart) styleDefaultsElements() Style <span class="cov0" title="0">{
-        return Style{
-                Font: pc.GetFont(),
-        }
-}</span>
-
-func (pc PieChart) styleDefaultsTitle() Style <span class="cov0" title="0">{
-        return pc.TitleStyle.InheritFrom(Style{
-                FontColor:           pc.GetColorPalette().TextColor(),
-                Font:                pc.GetFont(),
-                FontSize:            pc.getTitleFontSize(),
-                TextHorizontalAlign: TextHorizontalAlignCenter,
-                TextVerticalAlign:   TextVerticalAlignTop,
-                TextWrap:            TextWrapWord,
-        })
-}</span>
-
-func (pc PieChart) getTitleFontSize() float64 <span class="cov0" title="0">{
-        effectiveDimension := util.Math.MinInt(pc.GetWidth(), pc.GetHeight())
-        if effectiveDimension &gt;= 2048 </span><span class="cov0" title="0">{
-                return 48
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt;= 1024 </span><span class="cov0" title="0">{
-                return 24
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt;= 512 </span><span class="cov0" title="0">{
-                return 18
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt;= 256 </span><span class="cov0" title="0">{
-                return 12
-        }</span>
-        <span class="cov0" title="0">return 10</span>
-}
-
-// GetColorPalette returns the color palette for the chart.
-func (pc PieChart) GetColorPalette() ColorPalette <span class="cov8" title="1">{
-        if pc.ColorPalette != nil </span><span class="cov0" title="0">{
-                return pc.ColorPalette
-        }</span>
-        <span class="cov8" title="1">return AlternateColorPalette</span>
-}
-
-// Box returns the chart bounds as a box.
-func (pc PieChart) Box() Box <span class="cov8" title="1">{
-        dpr := pc.Background.Padding.GetRight(DefaultBackgroundPadding.Right)
-        dpb := pc.Background.Padding.GetBottom(DefaultBackgroundPadding.Bottom)
-
-        return Box{
-                Top:    pc.Background.Padding.GetTop(DefaultBackgroundPadding.Top),
-                Left:   pc.Background.Padding.GetLeft(DefaultBackgroundPadding.Left),
-                Right:  pc.GetWidth() - dpr,
-                Bottom: pc.GetHeight() - dpb,
-        }
-}</span>
-</pre>
-		
-		<pre class="file" id="file45" style="display: none">package chart
-
-import (
-        "fmt"
-        "math"
-
-        "github.com/wcharczuk/go-chart/matrix"
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// Interface Assertions.
-var (
-        _ Series              = (*PolynomialRegressionSeries)(nil)
-        _ FirstValuesProvider = (*PolynomialRegressionSeries)(nil)
-        _ LastValuesProvider  = (*PolynomialRegressionSeries)(nil)
-)
-
-// PolynomialRegressionSeries implements a polynomial regression over a given
-// inner series.
-type PolynomialRegressionSeries struct {
-        Name  string
-        Style Style
-        YAxis YAxisType
-
-        Limit       int
-        Offset      int
-        Degree      int
-        InnerSeries ValuesProvider
-
-        coeffs []float64
-}
-
-// GetName returns the name of the time series.
-func (prs PolynomialRegressionSeries) GetName() string <span class="cov0" title="0">{
-        return prs.Name
-}</span>
-
-// GetStyle returns the line style.
-func (prs PolynomialRegressionSeries) GetStyle() Style <span class="cov0" title="0">{
-        return prs.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (prs PolynomialRegressionSeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return prs.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (prs PolynomialRegressionSeries) Len() int <span class="cov0" title="0">{
-        return util.Math.MinInt(prs.GetLimit(), prs.InnerSeries.Len()-prs.GetOffset())
-}</span>
-
-// GetLimit returns the window size.
-func (prs PolynomialRegressionSeries) GetLimit() int <span class="cov8" title="1">{
-        if prs.Limit == 0 </span><span class="cov8" title="1">{
-                return prs.InnerSeries.Len()
-        }</span>
-        <span class="cov0" title="0">return prs.Limit</span>
-}
-
-// GetEndIndex returns the effective limit end.
-func (prs PolynomialRegressionSeries) GetEndIndex() int <span class="cov8" title="1">{
-        windowEnd := prs.GetOffset() + prs.GetLimit()
-        innerSeriesLastIndex := prs.InnerSeries.Len() - 1
-        return util.Math.MinInt(windowEnd, innerSeriesLastIndex)
-}</span>
-
-// GetOffset returns the data offset.
-func (prs PolynomialRegressionSeries) GetOffset() int <span class="cov8" title="1">{
-        if prs.Offset == 0 </span><span class="cov8" title="1">{
-                return 0
-        }</span>
-        <span class="cov0" title="0">return prs.Offset</span>
-}
-
-// Validate validates the series.
-func (prs *PolynomialRegressionSeries) Validate() error <span class="cov0" title="0">{
-        if prs.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("linear regression series requires InnerSeries to be set")
-        }</span>
-
-        <span class="cov0" title="0">endIndex := prs.GetEndIndex()
-        if endIndex &gt;= prs.InnerSeries.Len() </span><span class="cov0" title="0">{
-                return fmt.Errorf("invalid window; inner series has length %d but end index is %d", prs.InnerSeries.Len(), endIndex)
-        }</span>
-
-        <span class="cov0" title="0">return nil</span>
-}
-
-// GetValues returns the series value for a given index.
-func (prs *PolynomialRegressionSeries) GetValues(index int) (x, y float64) <span class="cov8" title="1">{
-        if prs.InnerSeries == nil || prs.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        <span class="cov8" title="1">if prs.coeffs == nil </span><span class="cov8" title="1">{
-                coeffs, err := prs.computeCoefficients()
-                if err != nil </span><span class="cov0" title="0">{
-                        panic(err)</span>
-                }
-                <span class="cov8" title="1">prs.coeffs = coeffs</span>
-        }
-
-        <span class="cov8" title="1">offset := prs.GetOffset()
-        effectiveIndex := util.Math.MinInt(index+offset, prs.InnerSeries.Len())
-        x, y = prs.InnerSeries.GetValues(effectiveIndex)
-        y = prs.apply(x)
-        return</span>
-}
-
-// GetFirstValues computes the first poly regression value.
-func (prs *PolynomialRegressionSeries) GetFirstValues() (x, y float64) <span class="cov0" title="0">{
-        if prs.InnerSeries == nil || prs.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">if prs.coeffs == nil </span><span class="cov0" title="0">{
-                coeffs, err := prs.computeCoefficients()
-                if err != nil </span><span class="cov0" title="0">{
-                        panic(err)</span>
-                }
-                <span class="cov0" title="0">prs.coeffs = coeffs</span>
-        }
-        <span class="cov0" title="0">x, y = prs.InnerSeries.GetValues(0)
-        y = prs.apply(x)
-        return</span>
-}
-
-// GetLastValues computes the last poly regression value.
-func (prs *PolynomialRegressionSeries) GetLastValues() (x, y float64) <span class="cov0" title="0">{
-        if prs.InnerSeries == nil || prs.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">if prs.coeffs == nil </span><span class="cov0" title="0">{
-                coeffs, err := prs.computeCoefficients()
-                if err != nil </span><span class="cov0" title="0">{
-                        panic(err)</span>
-                }
-                <span class="cov0" title="0">prs.coeffs = coeffs</span>
-        }
-        <span class="cov0" title="0">endIndex := prs.GetEndIndex()
-        x, y = prs.InnerSeries.GetValues(endIndex)
-        y = prs.apply(x)
-        return</span>
-}
-
-func (prs *PolynomialRegressionSeries) apply(v float64) (out float64) <span class="cov8" title="1">{
-        for index, coeff := range prs.coeffs </span><span class="cov8" title="1">{
-                out = out + (coeff * math.Pow(v, float64(index)))
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-func (prs *PolynomialRegressionSeries) computeCoefficients() ([]float64, error) <span class="cov8" title="1">{
-        xvalues, yvalues := prs.values()
-        return matrix.Poly(xvalues, yvalues, prs.Degree)
-}</span>
-
-func (prs *PolynomialRegressionSeries) values() (xvalues, yvalues []float64) <span class="cov8" title="1">{
-        startIndex := prs.GetOffset()
-        endIndex := prs.GetEndIndex()
-
-        xvalues = make([]float64, endIndex-startIndex)
-        yvalues = make([]float64, endIndex-startIndex)
-
-        for index := startIndex; index &lt; endIndex; index++ </span><span class="cov8" title="1">{
-                x, y := prs.InnerSeries.GetValues(index)
-                xvalues[index-startIndex] = x
-                yvalues[index-startIndex] = y
-        }</span>
-
-        <span class="cov8" title="1">return</span>
-}
-
-// Render renders the series.
-func (prs *PolynomialRegressionSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := prs.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, prs)
-}</span>
-</pre>
-		
-		<pre class="file" id="file46" style="display: none">package chart
-
-import (
-        "image"
-        "image/png"
-        "io"
-        "math"
-
-        "github.com/golang/freetype/truetype"
-        "github.com/wcharczuk/go-chart/drawing"
-        "github.com/wcharczuk/go-chart/util"
-)
-
-// PNG returns a new png/raster renderer.
-func PNG(width, height int) (Renderer, error) <span class="cov8" title="1">{
-        i := image.NewRGBA(image.Rect(0, 0, width, height))
-        gc, err := drawing.NewRasterGraphicContext(i)
-        if err == nil </span><span class="cov8" title="1">{
-                return &amp;rasterRenderer{
-                        i:  i,
-                        gc: gc,
-                }, nil
-        }</span>
-        <span class="cov0" title="0">return nil, err</span>
-}
-
-// rasterRenderer renders chart commands to a bitmap.
-type rasterRenderer struct {
-        i  *image.RGBA
-        gc *drawing.RasterGraphicContext
-
-        rotateRadians *float64
-
-        s Style
-}
-
-func (rr *rasterRenderer) ResetStyle() <span class="cov8" title="1">{
-        rr.s = Style{Font: rr.s.Font}
-        rr.ClearTextRotation()
-}</span>
-
-// GetDPI returns the dpi.
-func (rr *rasterRenderer) GetDPI() float64 <span class="cov0" title="0">{
-        return rr.gc.GetDPI()
-}</span>
-
-// SetDPI implements the interface method.
-func (rr *rasterRenderer) SetDPI(dpi float64) <span class="cov8" title="1">{
-        rr.gc.SetDPI(dpi)
-}</span>
-
-// SetClassName implements the interface method. However, PNGs have no classes.
-func (vr *rasterRenderer) SetClassName(_ string) {<span class="cov8" title="1">
-}</span>
-
-// SetStrokeColor implements the interface method.
-func (rr *rasterRenderer) SetStrokeColor(c drawing.Color) <span class="cov8" title="1">{
-        rr.s.StrokeColor = c
-}</span>
-
-// SetLineWidth implements the interface method.
-func (rr *rasterRenderer) SetStrokeWidth(width float64) <span class="cov8" title="1">{
-        rr.s.StrokeWidth = width
-}</span>
-
-// StrokeDashArray sets the stroke dash array.
-func (rr *rasterRenderer) SetStrokeDashArray(dashArray []float64) <span class="cov8" title="1">{
-        rr.s.StrokeDashArray = dashArray
-}</span>
-
-// SetFillColor implements the interface method.
-func (rr *rasterRenderer) SetFillColor(c drawing.Color) <span class="cov8" title="1">{
-        rr.s.FillColor = c
-}</span>
-
-// MoveTo implements the interface method.
-func (rr *rasterRenderer) MoveTo(x, y int) <span class="cov8" title="1">{
-        rr.gc.MoveTo(float64(x), float64(y))
-}</span>
-
-// LineTo implements the interface method.
-func (rr *rasterRenderer) LineTo(x, y int) <span class="cov8" title="1">{
-        rr.gc.LineTo(float64(x), float64(y))
-}</span>
-
-// QuadCurveTo implements the interface method.
-func (rr *rasterRenderer) QuadCurveTo(cx, cy, x, y int) <span class="cov0" title="0">{
-        rr.gc.QuadCurveTo(float64(cx), float64(cy), float64(x), float64(y))
-}</span>
-
-// ArcTo implements the interface method.
-func (rr *rasterRenderer) ArcTo(cx, cy int, rx, ry, startAngle, delta float64) <span class="cov8" title="1">{
-        rr.gc.ArcTo(float64(cx), float64(cy), rx, ry, startAngle, delta)
-}</span>
-
-// Close implements the interface method.
-func (rr *rasterRenderer) Close() <span class="cov8" title="1">{
-        rr.gc.Close()
-}</span>
-
-// Stroke implements the interface method.
-func (rr *rasterRenderer) Stroke() <span class="cov8" title="1">{
-        rr.gc.SetStrokeColor(rr.s.StrokeColor)
-        rr.gc.SetLineWidth(rr.s.StrokeWidth)
-        rr.gc.SetLineDash(rr.s.StrokeDashArray, 0)
-        rr.gc.Stroke()
-}</span>
-
-// Fill implements the interface method.
-func (rr *rasterRenderer) Fill() <span class="cov8" title="1">{
-        rr.gc.SetFillColor(rr.s.FillColor)
-        rr.gc.Fill()
-}</span>
-
-// FillStroke implements the interface method.
-func (rr *rasterRenderer) FillStroke() <span class="cov8" title="1">{
-        rr.gc.SetFillColor(rr.s.FillColor)
-        rr.gc.SetStrokeColor(rr.s.StrokeColor)
-        rr.gc.SetLineWidth(rr.s.StrokeWidth)
-        rr.gc.SetLineDash(rr.s.StrokeDashArray, 0)
-        rr.gc.FillStroke()
-}</span>
-
-// Circle fully draws a circle at a given point but does not apply the fill or stroke.
-func (rr *rasterRenderer) Circle(radius float64, x, y int) <span class="cov0" title="0">{
-        xf := float64(x)
-        yf := float64(y)
-
-        rr.gc.MoveTo(xf-radius, yf)                            //9
-        rr.gc.QuadCurveTo(xf-radius, yf-radius, xf, yf-radius) //12
-        rr.gc.QuadCurveTo(xf+radius, yf-radius, xf+radius, yf) //3
-        rr.gc.QuadCurveTo(xf+radius, yf+radius, xf, yf+radius) //6
-        rr.gc.QuadCurveTo(xf-radius, yf+radius, xf-radius, yf) //9
-}</span>
-
-// SetFont implements the interface method.
-func (rr *rasterRenderer) SetFont(f *truetype.Font) <span class="cov8" title="1">{
-        rr.s.Font = f
-}</span>
-
-// SetFontSize implements the interface method.
-func (rr *rasterRenderer) SetFontSize(size float64) <span class="cov8" title="1">{
-        rr.s.FontSize = size
-}</span>
-
-// SetFontColor implements the interface method.
-func (rr *rasterRenderer) SetFontColor(c drawing.Color) <span class="cov8" title="1">{
-        rr.s.FontColor = c
-}</span>
-
-// Text implements the interface method.
-func (rr *rasterRenderer) Text(body string, x, y int) <span class="cov8" title="1">{
-        xf, yf := rr.getCoords(x, y)
-        rr.gc.SetFont(rr.s.Font)
-        rr.gc.SetFontSize(rr.s.FontSize)
-        rr.gc.SetFillColor(rr.s.FontColor)
-        rr.gc.CreateStringPath(body, float64(xf), float64(yf))
-        rr.gc.Fill()
-}</span>
-
-// MeasureText returns the height and width in pixels of a string.
-func (rr *rasterRenderer) MeasureText(body string) Box <span class="cov8" title="1">{
-        rr.gc.SetFont(rr.s.Font)
-        rr.gc.SetFontSize(rr.s.FontSize)
-        rr.gc.SetFillColor(rr.s.FontColor)
-        l, t, r, b, err := rr.gc.GetStringBounds(body)
-        if err != nil </span><span class="cov8" title="1">{
-                return Box{}
-        }</span>
-        <span class="cov8" title="1">if l &lt; 0 </span><span class="cov0" title="0">{
-                r = r - l // equivalent to r+(-1*l)
-                l = 0
-        }</span>
-        <span class="cov8" title="1">if t &lt; 0 </span><span class="cov8" title="1">{
-                b = b - t
-                t = 0
-        }</span>
-
-        <span class="cov8" title="1">if l &gt; 0 </span><span class="cov8" title="1">{
-                r = r + l
-                l = 0
-        }</span>
-
-        <span class="cov8" title="1">if t &gt; 0 </span><span class="cov0" title="0">{
-                b = b + t
-                t = 0
-        }</span>
-
-        <span class="cov8" title="1">textBox := Box{
-                Top:    int(math.Ceil(t)),
-                Left:   int(math.Ceil(l)),
-                Right:  int(math.Ceil(r)),
-                Bottom: int(math.Ceil(b)),
-        }
-        if rr.rotateRadians == nil </span><span class="cov8" title="1">{
-                return textBox
-        }</span>
-
-        <span class="cov0" title="0">return textBox.Corners().Rotate(util.Math.RadiansToDegrees(*rr.rotateRadians)).Box()</span>
-}
-
-// SetTextRotation sets a text rotation.
-func (rr *rasterRenderer) SetTextRotation(radians float64) <span class="cov0" title="0">{
-        rr.rotateRadians = &amp;radians
-}</span>
-
-func (rr *rasterRenderer) getCoords(x, y int) (xf, yf int) <span class="cov8" title="1">{
-        if rr.rotateRadians == nil </span><span class="cov8" title="1">{
-                xf = x
-                yf = y
-                return
-        }</span>
-
-        <span class="cov0" title="0">rr.gc.Translate(float64(x), float64(y))
-        rr.gc.Rotate(*rr.rotateRadians)
-        return</span>
-}
-
-// ClearTextRotation clears text rotation.
-func (rr *rasterRenderer) ClearTextRotation() <span class="cov8" title="1">{
-        rr.gc.SetMatrixTransform(drawing.NewIdentityMatrix())
-        rr.rotateRadians = nil
-}</span>
-
-// Save implements the interface method.
-func (rr *rasterRenderer) Save(w io.Writer) error <span class="cov8" title="1">{
-        if typed, isTyped := w.(RGBACollector); isTyped </span><span class="cov0" title="0">{
-                typed.SetRGBA(rr.i)
-                return nil
-        }</span>
-        <span class="cov8" title="1">return png.Encode(w, rr.i)</span>
-}
-</pre>
-		
-		<pre class="file" id="file47" style="display: none">package seq
-
-// NewArray creates a new array.
-func NewArray(values ...float64) Array <span class="cov8" title="1">{
-        return Array(values)
-}</span>
-
-// Array is a wrapper for an array of floats that implements `ValuesProvider`.
-type Array []float64
-
-// Len returns the value provider length.
-func (a Array) Len() int <span class="cov8" title="1">{
-        return len(a)
-}</span>
-
-// GetValue returns the value at a given index.
-func (a Array) GetValue(index int) float64 <span class="cov8" title="1">{
-        return a[index]
-}</span>
-</pre>
-		
-		<pre class="file" id="file48" style="display: none">package seq
-
-import (
-        "fmt"
-        "strings"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-const (
-        bufferMinimumGrow     = 4
-        bufferShrinkThreshold = 32
-        bufferGrowFactor      = 200
-        bufferDefaultCapacity = 4
-)
-
-var (
-        emptyArray = make([]float64, 0)
-)
-
-// NewBuffer creates a new value buffer with an optional set of values.
-func NewBuffer(values ...float64) *Buffer <span class="cov8" title="1">{
-        var tail int
-        array := make([]float64, util.Math.MaxInt(len(values), bufferDefaultCapacity))
-        if len(values) &gt; 0 </span><span class="cov8" title="1">{
-                copy(array, values)
-                tail = len(values)
-        }</span>
-        <span class="cov8" title="1">return &amp;Buffer{
-                array: array,
-                head:  0,
-                tail:  tail,
-                size:  len(values),
-        }</span>
-}
-
-// NewBufferWithCapacity creates a new ValueBuffer pre-allocated with the given capacity.
-func NewBufferWithCapacity(capacity int) *Buffer <span class="cov0" title="0">{
-        return &amp;Buffer{
-                array: make([]float64, capacity),
-                head:  0,
-                tail:  0,
-                size:  0,
-        }
-}</span>
-
-// Buffer is a fifo datastructure that is backed by a pre-allocated array.
-// Instead of allocating a whole new node object for each element, array elements are re-used (which saves GC churn).
-// Enqueue can be O(n), Dequeue is generally O(1).
-// Buffer implements `seq.Provider`
-type Buffer struct {
-        array []float64
-        head  int
-        tail  int
-        size  int
-}
-
-// Len returns the length of the Buffer (as it is currently populated).
-// Actual memory footprint may be different.
-func (b *Buffer) Len() int <span class="cov8" title="1">{
-        return b.size
-}</span>
-
-// GetValue implements seq provider.
-func (b *Buffer) GetValue(index int) float64 <span class="cov0" title="0">{
-        effectiveIndex := (b.head + index) % len(b.array)
-        return b.array[effectiveIndex]
-}</span>
-
-// Capacity returns the total size of the Buffer, including empty elements.
-func (b *Buffer) Capacity() int <span class="cov8" title="1">{
-        return len(b.array)
-}</span>
-
-// SetCapacity sets the capacity of the Buffer.
-func (b *Buffer) SetCapacity(capacity int) <span class="cov8" title="1">{
-        newArray := make([]float64, capacity)
-        if b.size &gt; 0 </span><span class="cov8" title="1">{
-                if b.head &lt; b.tail </span><span class="cov8" title="1">{
-                        arrayCopy(b.array, b.head, newArray, 0, b.size)
-                }</span> else<span class="cov8" title="1"> {
-                        arrayCopy(b.array, b.head, newArray, 0, len(b.array)-b.head)
-                        arrayCopy(b.array, 0, newArray, len(b.array)-b.head, b.tail)
-                }</span>
-        }
-        <span class="cov8" title="1">b.array = newArray
-        b.head = 0
-        if b.size == capacity </span><span class="cov0" title="0">{
-                b.tail = 0
-        }</span> else<span class="cov8" title="1"> {
-                b.tail = b.size
-        }</span>
-}
-
-// Clear removes all objects from the Buffer.
-func (b *Buffer) Clear() <span class="cov8" title="1">{
-        b.array = make([]float64, bufferDefaultCapacity)
-        b.head = 0
-        b.tail = 0
-        b.size = 0
-}</span>
-
-// Enqueue adds an element to the "back" of the Buffer.
-func (b *Buffer) Enqueue(value float64) <span class="cov8" title="1">{
-        if b.size == len(b.array) </span><span class="cov8" title="1">{
-                newCapacity := int(len(b.array) * int(bufferGrowFactor/100))
-                if newCapacity &lt; (len(b.array) + bufferMinimumGrow) </span><span class="cov0" title="0">{
-                        newCapacity = len(b.array) + bufferMinimumGrow
-                }</span>
-                <span class="cov8" title="1">b.SetCapacity(newCapacity)</span>
-        }
-
-        <span class="cov8" title="1">b.array[b.tail] = value
-        b.tail = (b.tail + 1) % len(b.array)
-        b.size++</span>
-}
-
-// Dequeue removes the first element from the RingBuffer.
-func (b *Buffer) Dequeue() float64 <span class="cov8" title="1">{
-        if b.size == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">removed := b.array[b.head]
-        b.head = (b.head + 1) % len(b.array)
-        b.size--
-        return removed</span>
-}
-
-// Peek returns but does not remove the first element.
-func (b *Buffer) Peek() float64 <span class="cov8" title="1">{
-        if b.size == 0 </span><span class="cov8" title="1">{
-                return 0
-        }</span>
-        <span class="cov8" title="1">return b.array[b.head]</span>
-}
-
-// PeekBack returns but does not remove the last element.
-func (b *Buffer) PeekBack() float64 <span class="cov8" title="1">{
-        if b.size == 0 </span><span class="cov8" title="1">{
-                return 0
-        }</span>
-        <span class="cov8" title="1">if b.tail == 0 </span><span class="cov8" title="1">{
-                return b.array[len(b.array)-1]
-        }</span>
-        <span class="cov8" title="1">return b.array[b.tail-1]</span>
-}
-
-// TrimExcess resizes the capacity of the buffer to better fit the contents.
-func (b *Buffer) TrimExcess() <span class="cov0" title="0">{
-        threshold := float64(len(b.array)) * 0.9
-        if b.size &lt; int(threshold) </span><span class="cov0" title="0">{
-                b.SetCapacity(b.size)
-        }</span>
-}
-
-// Array returns the ring buffer, in order, as an array.
-func (b *Buffer) Array() Array <span class="cov8" title="1">{
-        newArray := make([]float64, b.size)
-
-        if b.size == 0 </span><span class="cov0" title="0">{
-                return newArray
-        }</span>
-
-        <span class="cov8" title="1">if b.head &lt; b.tail </span><span class="cov8" title="1">{
-                arrayCopy(b.array, b.head, newArray, 0, b.size)
-        }</span> else<span class="cov0" title="0"> {
-                arrayCopy(b.array, b.head, newArray, 0, len(b.array)-b.head)
-                arrayCopy(b.array, 0, newArray, len(b.array)-b.head, b.tail)
-        }</span>
-
-        <span class="cov8" title="1">return Array(newArray)</span>
-}
-
-// Each calls the consumer for each element in the buffer.
-func (b *Buffer) Each(mapfn func(int, float64)) <span class="cov8" title="1">{
-        if b.size == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        <span class="cov8" title="1">var index int
-        if b.head &lt; b.tail </span><span class="cov0" title="0">{
-                for cursor := b.head; cursor &lt; b.tail; cursor++ </span><span class="cov0" title="0">{
-                        mapfn(index, b.array[cursor])
-                        index++
-                }</span>
-        } else<span class="cov8" title="1"> {
-                for cursor := b.head; cursor &lt; len(b.array); cursor++ </span><span class="cov8" title="1">{
-                        mapfn(index, b.array[cursor])
-                        index++
-                }</span>
-                <span class="cov8" title="1">for cursor := 0; cursor &lt; b.tail; cursor++ </span><span class="cov0" title="0">{
-                        mapfn(index, b.array[cursor])
-                        index++
-                }</span>
-        }
-}
-
-// String returns a string representation for value buffers.
-func (b *Buffer) String() string <span class="cov0" title="0">{
-        var values []string
-        for _, elem := range b.Array() </span><span class="cov0" title="0">{
-                values = append(values, fmt.Sprintf("%v", elem))
-        }</span>
-        <span class="cov0" title="0">return strings.Join(values, " &lt;= ")</span>
-}
-
-// --------------------------------------------------------------------------------
-// Util methods
-// --------------------------------------------------------------------------------
-
-func arrayClear(source []float64, index, length int) <span class="cov0" title="0">{
-        for x := 0; x &lt; length; x++ </span><span class="cov0" title="0">{
-                absoluteIndex := x + index
-                source[absoluteIndex] = 0
-        }</span>
-}
-
-func arrayCopy(source []float64, sourceIndex int, destination []float64, destinationIndex, length int) <span class="cov8" title="1">{
-        for x := 0; x &lt; length; x++ </span><span class="cov8" title="1">{
-                from := sourceIndex + x
-                to := destinationIndex + x
-
-                destination[to] = source[from]
-        }</span>
-}
-</pre>
-		
-		<pre class="file" id="file49" style="display: none">package seq
-
-// Range returns the array values of a linear seq with a given start, end and optional step.
-func Range(start, end float64) []float64 <span class="cov8" title="1">{
-        return Seq{NewLinear().WithStart(start).WithEnd(end).WithStep(1.0)}.Array()
-}</span>
-
-// RangeWithStep returns the array values of a linear seq with a given start, end and optional step.
-func RangeWithStep(start, end, step float64) []float64 <span class="cov8" title="1">{
-        return Seq{NewLinear().WithStart(start).WithEnd(end).WithStep(step)}.Array()
-}</span>
-
-// NewLinear returns a new linear generator.
-func NewLinear() *Linear <span class="cov8" title="1">{
-        return &amp;Linear{step: 1.0}
-}</span>
-
-// Linear is a stepwise generator.
-type Linear struct {
-        start float64
-        end   float64
-        step  float64
-}
-
-// Start returns the start value.
-func (lg Linear) Start() float64 <span class="cov8" title="1">{
-        return lg.start
-}</span>
-
-// End returns the end value.
-func (lg Linear) End() float64 <span class="cov8" title="1">{
-        return lg.end
-}</span>
-
-// Step returns the step value.
-func (lg Linear) Step() float64 <span class="cov0" title="0">{
-        return lg.step
-}</span>
-
-// Len returns the number of elements in the seq.
-func (lg Linear) Len() int <span class="cov8" title="1">{
-        if lg.start &lt; lg.end </span><span class="cov8" title="1">{
-                return int((lg.end-lg.start)/lg.step) + 1
-        }</span>
-        <span class="cov8" title="1">return int((lg.start-lg.end)/lg.step) + 1</span>
-}
-
-// GetValue returns the value at a given index.
-func (lg Linear) GetValue(index int) float64 <span class="cov8" title="1">{
-        fi := float64(index)
-        if lg.start &lt; lg.end </span><span class="cov8" title="1">{
-                return lg.start + (fi * lg.step)
-        }</span>
-        <span class="cov8" title="1">return lg.start - (fi * lg.step)</span>
-}
-
-// WithStart sets the start and returns the linear generator.
-func (lg *Linear) WithStart(start float64) *Linear <span class="cov8" title="1">{
-        lg.start = start
-        return lg
-}</span>
-
-// WithEnd sets the end and returns the linear generator.
-func (lg *Linear) WithEnd(end float64) *Linear <span class="cov8" title="1">{
-        lg.end = end
-        return lg
-}</span>
-
-// WithStep sets the step and returns the linear generator.
-func (lg *Linear) WithStep(step float64) *Linear <span class="cov8" title="1">{
-        lg.step = step
-        return lg
-}</span>
-</pre>
-		
-		<pre class="file" id="file50" style="display: none">package seq
-
-import (
-        "math"
-        "math/rand"
-        "time"
-)
-
-// RandomValues returns an array of random values.
-func RandomValues(count int) []float64 <span class="cov0" title="0">{
-        return Seq{NewRandom().WithLen(count)}.Array()
-}</span>
-
-// RandomValuesWithMax returns an array of random values with a given average.
-func RandomValuesWithMax(count int, max float64) []float64 <span class="cov0" title="0">{
-        return Seq{NewRandom().WithMax(max).WithLen(count)}.Array()
-}</span>
-
-// NewRandom creates a new random seq.
-func NewRandom() *Random <span class="cov8" title="1">{
-        return &amp;Random{
-                rnd: rand.New(rand.NewSource(time.Now().Unix())),
-        }
-}</span>
-
-// Random is a random number seq generator.
-type Random struct {
-        rnd *rand.Rand
-        max *float64
-        min *float64
-        len *int
-}
-
-// Len returns the number of elements that will be generated.
-func (r *Random) Len() int <span class="cov8" title="1">{
-        if r.len != nil </span><span class="cov8" title="1">{
-                return *r.len
-        }</span>
-        <span class="cov0" title="0">return math.MaxInt32</span>
-}
-
-// GetValue returns the value.
-func (r *Random) GetValue(_ int) float64 <span class="cov8" title="1">{
-        if r.min != nil &amp;&amp; r.max != nil </span><span class="cov0" title="0">{
-                var delta float64
-
-                if *r.max &gt; *r.min </span><span class="cov0" title="0">{
-                        delta = *r.max - *r.min
-                }</span> else<span class="cov0" title="0"> {
-                        delta = *r.min - *r.max
-                }</span>
-
-                <span class="cov0" title="0">return *r.min + (r.rnd.Float64() * delta)</span>
-        } else<span class="cov8" title="1"> if r.max != nil </span><span class="cov8" title="1">{
-                return r.rnd.Float64() * *r.max
-        }</span> else<span class="cov0" title="0"> if r.min != nil </span><span class="cov0" title="0">{
-                return *r.min + (r.rnd.Float64())
-        }</span>
-        <span class="cov0" title="0">return r.rnd.Float64()</span>
-}
-
-// WithLen sets a maximum len
-func (r *Random) WithLen(length int) *Random <span class="cov8" title="1">{
-        r.len = &amp;length
-        return r
-}</span>
-
-// Min returns the minimum value.
-func (r Random) Min() *float64 <span class="cov0" title="0">{
-        return r.min
-}</span>
-
-// WithMin sets the scale and returns the Random.
-func (r *Random) WithMin(min float64) *Random <span class="cov0" title="0">{
-        r.min = &amp;min
-        return r
-}</span>
-
-// Max returns the maximum value.
-func (r Random) Max() *float64 <span class="cov8" title="1">{
-        return r.max
-}</span>
-
-// WithMax sets the average and returns the Random.
-func (r *Random) WithMax(max float64) *Random <span class="cov8" title="1">{
-        r.max = &amp;max
-        return r
-}</span>
-</pre>
-		
-		<pre class="file" id="file51" style="display: none">package seq
-
-import (
-        "math"
-        "sort"
-)
-
-// New wraps a provider with a seq.
-func New(provider Provider) Seq <span class="cov8" title="1">{
-        return Seq{Provider: provider}
-}</span>
-
-// Values returns a new seq composed of a given set of values.
-func Values(values ...float64) Seq <span class="cov8" title="1">{
-        return Seq{Provider: Array(values)}
-}</span>
-
-// Provider is a provider for values for a seq.
-type Provider interface {
-        Len() int
-        GetValue(int) float64
-}
-
-// Seq is a utility wrapper for seq providers.
-type Seq struct {
-        Provider
-}
-
-// Array enumerates the seq into a slice.
-func (s Seq) Array() (output []float64) <span class="cov8" title="1">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        <span class="cov8" title="1">output = make([]float64, s.Len())
-        for i := 0; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                output[i] = s.GetValue(i)
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// Each applies the `mapfn` to all values in the value provider.
-func (s Seq) Each(mapfn func(int, float64)) <span class="cov8" title="1">{
-        for i := 0; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                mapfn(i, s.GetValue(i))
-        }</span>
-}
-
-// Map applies the `mapfn` to all values in the value provider,
-// returning a new seq.
-func (s Seq) Map(mapfn func(i int, v float64) float64) Seq <span class="cov8" title="1">{
-        output := make([]float64, s.Len())
-        for i := 0; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                mapfn(i, s.GetValue(i))
-        }</span>
-        <span class="cov8" title="1">return Seq{Array(output)}</span>
-}
-
-// FoldLeft collapses a seq from left to right.
-func (s Seq) FoldLeft(mapfn func(i int, v0, v float64) float64) (v0 float64) <span class="cov8" title="1">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">if s.Len() == 1 </span><span class="cov0" title="0">{
-                return s.GetValue(0)
-        }</span>
-
-        <span class="cov8" title="1">v0 = s.GetValue(0)
-        for i := 1; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                v0 = mapfn(i, v0, s.GetValue(i))
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// FoldRight collapses a seq from right to left.
-func (s Seq) FoldRight(mapfn func(i int, v0, v float64) float64) (v0 float64) <span class="cov8" title="1">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">if s.Len() == 1 </span><span class="cov0" title="0">{
-                return s.GetValue(0)
-        }</span>
-
-        <span class="cov8" title="1">v0 = s.GetValue(s.Len() - 1)
-        for i := s.Len() - 2; i &gt;= 0; i-- </span><span class="cov8" title="1">{
-                v0 = mapfn(i, v0, s.GetValue(i))
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// Min returns the minimum value in the seq.
-func (s Seq) Min() float64 <span class="cov0" title="0">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-        <span class="cov0" title="0">min := s.GetValue(0)
-        var value float64
-        for i := 1; i &lt; s.Len(); i++ </span><span class="cov0" title="0">{
-                value = s.GetValue(i)
-                if value &lt; min </span><span class="cov0" title="0">{
-                        min = value
-                }</span>
-        }
-        <span class="cov0" title="0">return min</span>
-}
-
-// Max returns the maximum value in the seq.
-func (s Seq) Max() float64 <span class="cov0" title="0">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-        <span class="cov0" title="0">max := s.GetValue(0)
-        var value float64
-        for i := 1; i &lt; s.Len(); i++ </span><span class="cov0" title="0">{
-                value = s.GetValue(i)
-                if value &gt; max </span><span class="cov0" title="0">{
-                        max = value
-                }</span>
-        }
-        <span class="cov0" title="0">return max</span>
-}
-
-// MinMax returns the minimum and the maximum in one pass.
-func (s Seq) MinMax() (min, max float64) <span class="cov8" title="1">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">min = s.GetValue(0)
-        max = min
-        var value float64
-        for i := 1; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                value = s.GetValue(i)
-                if value &lt; min </span><span class="cov0" title="0">{
-                        min = value
-                }</span>
-                <span class="cov8" title="1">if value &gt; max </span><span class="cov8" title="1">{
-                        max = value
-                }</span>
-        }
-        <span class="cov8" title="1">return</span>
-}
-
-// Sort returns the seq sorted in ascending order.
-// This fully enumerates the seq.
-func (s Seq) Sort() Seq <span class="cov0" title="0">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return s
-        }</span>
-        <span class="cov0" title="0">values := s.Array()
-        sort.Float64s(values)
-        return Seq{Provider: Array(values)}</span>
-}
-
-// Median returns the median or middle value in the sorted seq.
-func (s Seq) Median() (median float64) <span class="cov0" title="0">{
-        l := s.Len()
-        if l == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-
-        <span class="cov0" title="0">sorted := s.Sort()
-        if l%2 == 0 </span><span class="cov0" title="0">{
-                v0 := sorted.GetValue(l/2 - 1)
-                v1 := sorted.GetValue(l/2 + 1)
-                median = (v0 + v1) / 2
-        }</span> else<span class="cov0" title="0"> {
-                median = float64(sorted.GetValue(l &lt;&lt; 1))
-        }</span>
-
-        <span class="cov0" title="0">return</span>
-}
-
-// Sum adds all the elements of a series together.
-func (s Seq) Sum() (accum float64) <span class="cov8" title="1">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">for i := 0; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                accum += s.GetValue(i)
-        }</span>
-        <span class="cov8" title="1">return</span>
-}
-
-// Average returns the float average of the values in the buffer.
-func (s Seq) Average() float64 <span class="cov8" title="1">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">return s.Sum() / float64(s.Len())</span>
-}
-
-// Variance computes the variance of the buffer.
-func (s Seq) Variance() float64 <span class="cov8" title="1">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov8" title="1">m := s.Average()
-        var variance, v float64
-        for i := 0; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                v = s.GetValue(i)
-                variance += (v - m) * (v - m)
-        }</span>
-
-        <span class="cov8" title="1">return variance / float64(s.Len())</span>
-}
-
-// StdDev returns the standard deviation.
-func (s Seq) StdDev() float64 <span class="cov0" title="0">{
-        if s.Len() == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov0" title="0">return math.Pow(s.Variance(), 0.5)</span>
-}
-
-//Percentile finds the relative standing in a slice of floats.
-// `percent` should be given on the interval [0,1.0).
-func (s Seq) Percentile(percent float64) (percentile float64) <span class="cov0" title="0">{
-        l := s.Len()
-        if l == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-
-        <span class="cov0" title="0">if percent &lt; 0 || percent &gt; 1.0 </span><span class="cov0" title="0">{
-                panic("percent out of range [0.0, 1.0)")</span>
-        }
-
-        <span class="cov0" title="0">sorted := s.Sort()
-        index := percent * float64(l)
-        if index == float64(int64(index)) </span><span class="cov0" title="0">{
-                i := f64i(index)
-                ci := sorted.GetValue(i - 1)
-                c := sorted.GetValue(i)
-                percentile = (ci + c) / 2.0
-        }</span> else<span class="cov0" title="0"> {
-                i := f64i(index)
-                percentile = sorted.GetValue(i)
-        }</span>
-
-        <span class="cov0" title="0">return percentile</span>
-}
-
-// Normalize maps every value to the interval [0, 1.0].
-func (s Seq) Normalize() Seq <span class="cov8" title="1">{
-        min, max := s.MinMax()
-
-        delta := max - min
-        output := make([]float64, s.Len())
-        for i := 0; i &lt; s.Len(); i++ </span><span class="cov8" title="1">{
-                output[i] = (s.GetValue(i) - min) / delta
-        }</span>
-
-        <span class="cov8" title="1">return Seq{Provider: Array(output)}</span>
-}
-</pre>
-		
-		<pre class="file" id="file52" style="display: none">package seq
-
-import (
-        "time"
-
-        "github.com/wcharczuk/go-chart/util"
-)
-
-// Time is a utility singleton with helper functions for time seq generation.
-var Time timeSequence
-
-type timeSequence struct{}
-
-// Days generates a seq of timestamps by day, from -days to today.
-func (ts timeSequence) Days(days int) []time.Time <span class="cov0" title="0">{
-        var values []time.Time
-        for day := days; day &gt;= 0; day-- </span><span class="cov0" title="0">{
-                values = append(values, time.Now().AddDate(0, 0, -day))
-        }</span>
-        <span class="cov0" title="0">return values</span>
-}
-
-func (ts timeSequence) Hours(start time.Time, totalHours int) []time.Time <span class="cov8" title="1">{
-        times := make([]time.Time, totalHours)
-
-        last := start
-        for i := 0; i &lt; totalHours; i++ </span><span class="cov8" title="1">{
-                times[i] = last
-                last = last.Add(time.Hour)
-        }</span>
-
-        <span class="cov8" title="1">return times</span>
-}
-
-// HoursFilled adds zero values for the data bounded by the start and end of the xdata array.
-func (ts timeSequence) HoursFilled(xdata []time.Time, ydata []float64) ([]time.Time, []float64) <span class="cov8" title="1">{
-        start, end := util.Time.StartAndEnd(xdata...)
-        totalHours := util.Time.DiffHours(start, end)
-
-        finalTimes := ts.Hours(start, totalHours+1)
-        finalValues := make([]float64, totalHours+1)
-
-        var hoursFromStart int
-        for i, xd := range xdata </span><span class="cov8" title="1">{
-                hoursFromStart = util.Time.DiffHours(start, xd)
-                finalValues[hoursFromStart] = ydata[i]
-        }</span>
-
-        <span class="cov8" title="1">return finalTimes, finalValues</span>
-}
-</pre>
-		
-		<pre class="file" id="file53" style="display: none">package seq
-
-import (
-        "time"
-
-        "github.com/wcharczuk/go-chart/util"
-)
-
-// Assert types implement interfaces.
-var (
-        _ Provider = (*Times)(nil)
-)
-
-// Times are an array of times.
-// It wraps the array with methods that implement `seq.Provider`.
-type Times []time.Time
-
-// Array returns the times to an array.
-func (t Times) Array() []time.Time <span class="cov0" title="0">{
-        return []time.Time(t)
-}</span>
-
-// Len returns the length of the array.
-func (t Times) Len() int <span class="cov0" title="0">{
-        return len(t)
-}</span>
-
-// GetValue returns a value at an index as a time.
-func (t Times) GetValue(index int) float64 <span class="cov0" title="0">{
-        return util.Time.ToFloat64(t[index])
-}</span>
-</pre>
-		
-		<pre class="file" id="file54" style="display: none">package seq
-
-import "math"
-
-func round(input float64, places int) (rounded float64) <span class="cov0" title="0">{
-        if math.IsNaN(input) </span><span class="cov0" title="0">{
-                return 0.0
-        }</span>
-
-        <span class="cov0" title="0">sign := 1.0
-        if input &lt; 0 </span><span class="cov0" title="0">{
-                sign = -1
-                input *= -1
-        }</span>
-
-        <span class="cov0" title="0">precision := math.Pow(10, float64(places))
-        digit := input * precision
-        _, decimal := math.Modf(digit)
-
-        if decimal &gt;= 0.5 </span><span class="cov0" title="0">{
-                rounded = math.Ceil(digit)
-        }</span> else<span class="cov0" title="0"> {
-                rounded = math.Floor(digit)
-        }</span>
-
-        <span class="cov0" title="0">return rounded / precision * sign</span>
-}
-
-func f64i(value float64) int <span class="cov0" title="0">{
-        r := round(value, 0)
-        return int(r)
-}</span>
-</pre>
-		
-		<pre class="file" id="file55" style="display: none">package chart
-
-import (
-        "fmt"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-const (
-        // DefaultSimpleMovingAveragePeriod is the default number of values to average.
-        DefaultSimpleMovingAveragePeriod = 16
-)
-
-// Interface Assertions.
-var (
-        _ Series              = (*SMASeries)(nil)
-        _ FirstValuesProvider = (*SMASeries)(nil)
-        _ LastValuesProvider  = (*SMASeries)(nil)
-)
-
-// SMASeries is a computed series.
-type SMASeries struct {
-        Name  string
-        Style Style
-        YAxis YAxisType
-
-        Period      int
-        InnerSeries ValuesProvider
-}
-
-// GetName returns the name of the time series.
-func (sma SMASeries) GetName() string <span class="cov0" title="0">{
-        return sma.Name
-}</span>
-
-// GetStyle returns the line style.
-func (sma SMASeries) GetStyle() Style <span class="cov0" title="0">{
-        return sma.Style
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (sma SMASeries) GetYAxis() YAxisType <span class="cov0" title="0">{
-        return sma.YAxis
-}</span>
-
-// Len returns the number of elements in the series.
-func (sma SMASeries) Len() int <span class="cov8" title="1">{
-        return sma.InnerSeries.Len()
-}</span>
-
-// GetPeriod returns the window size.
-func (sma SMASeries) GetPeriod(defaults ...int) int <span class="cov8" title="1">{
-        if sma.Period == 0 </span><span class="cov0" title="0">{
-                if len(defaults) &gt; 0 </span><span class="cov0" title="0">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return DefaultSimpleMovingAveragePeriod</span>
-        }
-        <span class="cov8" title="1">return sma.Period</span>
-}
-
-// GetValues gets a value at a given index.
-func (sma SMASeries) GetValues(index int) (x, y float64) <span class="cov8" title="1">{
-        if sma.InnerSeries == nil || sma.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">px, _ := sma.InnerSeries.GetValues(index)
-        x = px
-        y = sma.getAverage(index)
-        return</span>
-}
-
-// GetFirstValues computes the first moving average value.
-func (sma SMASeries) GetFirstValues() (x, y float64) <span class="cov0" title="0">{
-        if sma.InnerSeries == nil || sma.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov0" title="0">px, _ := sma.InnerSeries.GetValues(0)
-        x = px
-        y = sma.getAverage(0)
-        return</span>
-}
-
-// GetLastValues computes the last moving average value but walking back window size samples,
-// and recomputing the last moving average chunk.
-func (sma SMASeries) GetLastValues() (x, y float64) <span class="cov8" title="1">{
-        if sma.InnerSeries == nil || sma.InnerSeries.Len() == 0 </span><span class="cov0" title="0">{
-                return
-        }</span>
-        <span class="cov8" title="1">seriesLen := sma.InnerSeries.Len()
-        px, _ := sma.InnerSeries.GetValues(seriesLen - 1)
-        x = px
-        y = sma.getAverage(seriesLen - 1)
-        return</span>
-}
-
-func (sma SMASeries) getAverage(index int) float64 <span class="cov8" title="1">{
-        period := sma.GetPeriod()
-        floor := util.Math.MaxInt(0, index-period)
-        var accum float64
-        var count float64
-        for x := index; x &gt;= floor; x-- </span><span class="cov8" title="1">{
-                _, vy := sma.InnerSeries.GetValues(x)
-                accum += vy
-                count += 1.0
-        }</span>
-        <span class="cov8" title="1">return accum / count</span>
-}
-
-// Render renders the series.
-func (sma SMASeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov0" title="0">{
-        style := sma.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, sma)
-}</span>
-
-// Validate validates the series.
-func (sma SMASeries) Validate() error <span class="cov0" title="0">{
-        if sma.InnerSeries == nil </span><span class="cov0" title="0">{
-                return fmt.Errorf("sma series requires InnerSeries to be set")
-        }</span>
-        <span class="cov0" title="0">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file56" style="display: none">package chart
-
-import (
-        "errors"
-        "fmt"
-        "io"
-        "math"
-
-        "github.com/golang/freetype/truetype"
-        "github.com/wcharczuk/go-chart/seq"
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// StackedBar is a bar within a StackedBarChart.
-type StackedBar struct {
-        Name   string
-        Width  int
-        Values []Value
-}
-
-// GetWidth returns the width of the bar.
-func (sb StackedBar) GetWidth() int <span class="cov0" title="0">{
-        if sb.Width == 0 </span><span class="cov0" title="0">{
-                return 50
-        }</span>
-        <span class="cov0" title="0">return sb.Width</span>
-}
-
-// StackedBarChart is a chart that draws sections of a bar based on percentages.
-type StackedBarChart struct {
-        Title      string
-        TitleStyle Style
-
-        ColorPalette ColorPalette
-
-        Width  int
-        Height int
-        DPI    float64
-
-        Background Style
-        Canvas     Style
-
-        XAxis Style
-        YAxis Style
-
-        BarSpacing int
-
-        Font        *truetype.Font
-        defaultFont *truetype.Font
-
-        Bars     []StackedBar
-        Elements []Renderable
-}
-
-// GetDPI returns the dpi for the chart.
-func (sbc StackedBarChart) GetDPI(defaults ...float64) float64 <span class="cov0" title="0">{
-        if sbc.DPI == 0 </span><span class="cov0" title="0">{
-                if len(defaults) &gt; 0 </span><span class="cov0" title="0">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return DefaultDPI</span>
-        }
-        <span class="cov0" title="0">return sbc.DPI</span>
-}
-
-// GetFont returns the text font.
-func (sbc StackedBarChart) GetFont() *truetype.Font <span class="cov0" title="0">{
-        if sbc.Font == nil </span><span class="cov0" title="0">{
-                return sbc.defaultFont
-        }</span>
-        <span class="cov0" title="0">return sbc.Font</span>
-}
-
-// GetWidth returns the chart width or the default value.
-func (sbc StackedBarChart) GetWidth() int <span class="cov0" title="0">{
-        if sbc.Width == 0 </span><span class="cov0" title="0">{
-                return DefaultChartWidth
-        }</span>
-        <span class="cov0" title="0">return sbc.Width</span>
-}
-
-// GetHeight returns the chart height or the default value.
-func (sbc StackedBarChart) GetHeight() int <span class="cov0" title="0">{
-        if sbc.Height == 0 </span><span class="cov0" title="0">{
-                return DefaultChartWidth
-        }</span>
-        <span class="cov0" title="0">return sbc.Height</span>
-}
-
-// GetBarSpacing returns the spacing between bars.
-func (sbc StackedBarChart) GetBarSpacing() int <span class="cov0" title="0">{
-        if sbc.BarSpacing == 0 </span><span class="cov0" title="0">{
-                return 100
-        }</span>
-        <span class="cov0" title="0">return sbc.BarSpacing</span>
-}
-
-// Render renders the chart with the given renderer to the given io.Writer.
-func (sbc StackedBarChart) Render(rp RendererProvider, w io.Writer) error <span class="cov0" title="0">{
-        if len(sbc.Bars) == 0 </span><span class="cov0" title="0">{
-                return errors.New("please provide at least one bar")
-        }</span>
-
-        <span class="cov0" title="0">r, err := rp(sbc.GetWidth(), sbc.GetHeight())
-        if err != nil </span><span class="cov0" title="0">{
-                return err
-        }</span>
-
-        <span class="cov0" title="0">if sbc.Font == nil </span><span class="cov0" title="0">{
-                defaultFont, err := GetDefaultFont()
-                if err != nil </span><span class="cov0" title="0">{
-                        return err
-                }</span>
-                <span class="cov0" title="0">sbc.defaultFont = defaultFont</span>
-        }
-        <span class="cov0" title="0">r.SetDPI(sbc.GetDPI(DefaultDPI))
-
-        canvasBox := sbc.getAdjustedCanvasBox(r, sbc.getDefaultCanvasBox())
-        sbc.drawCanvas(r, canvasBox)
-        sbc.drawBars(r, canvasBox)
-        sbc.drawXAxis(r, canvasBox)
-        sbc.drawYAxis(r, canvasBox)
-
-        sbc.drawTitle(r)
-        for _, a := range sbc.Elements </span><span class="cov0" title="0">{
-                a(r, canvasBox, sbc.styleDefaultsElements())
-        }</span>
-
-        <span class="cov0" title="0">return r.Save(w)</span>
-}
-
-func (sbc StackedBarChart) drawCanvas(r Renderer, canvasBox Box) <span class="cov0" title="0">{
-        Draw.Box(r, canvasBox, sbc.getCanvasStyle())
-}</span>
-
-func (sbc StackedBarChart) drawBars(r Renderer, canvasBox Box) <span class="cov0" title="0">{
-        xoffset := canvasBox.Left
-        for _, bar := range sbc.Bars </span><span class="cov0" title="0">{
-                sbc.drawBar(r, canvasBox, xoffset, bar)
-                xoffset += (sbc.GetBarSpacing() + bar.GetWidth())
-        }</span>
-}
-
-func (sbc StackedBarChart) drawBar(r Renderer, canvasBox Box, xoffset int, bar StackedBar) int <span class="cov0" title="0">{
-        barSpacing2 := sbc.GetBarSpacing() &gt;&gt; 1
-        bxl := xoffset + barSpacing2
-        bxr := bxl + bar.GetWidth()
-
-        normalizedBarComponents := Values(bar.Values).Normalize()
-        yoffset := canvasBox.Top
-        for index, bv := range normalizedBarComponents </span><span class="cov0" title="0">{
-                barHeight := int(math.Ceil(bv.Value * float64(canvasBox.Height())))
-                barBox := Box{
-                        Top:    yoffset,
-                        Left:   bxl,
-                        Right:  bxr,
-                        Bottom: util.Math.MinInt(yoffset+barHeight, canvasBox.Bottom-DefaultStrokeWidth),
-                }
-                Draw.Box(r, barBox, bv.Style.InheritFrom(sbc.styleDefaultsStackedBarValue(index)))
-                yoffset += barHeight
-        }</span>
-
-        <span class="cov0" title="0">return bxr</span>
-}
-
-func (sbc StackedBarChart) drawXAxis(r Renderer, canvasBox Box) <span class="cov0" title="0">{
-        if sbc.XAxis.Show </span><span class="cov0" title="0">{
-                axisStyle := sbc.XAxis.InheritFrom(sbc.styleDefaultsAxes())
-                axisStyle.WriteToRenderer(r)
-
-                r.MoveTo(canvasBox.Left, canvasBox.Bottom)
-                r.LineTo(canvasBox.Right, canvasBox.Bottom)
-                r.Stroke()
-
-                r.MoveTo(canvasBox.Left, canvasBox.Bottom)
-                r.LineTo(canvasBox.Left, canvasBox.Bottom+DefaultVerticalTickHeight)
-                r.Stroke()
-
-                cursor := canvasBox.Left
-                for _, bar := range sbc.Bars </span><span class="cov0" title="0">{
-
-                        barLabelBox := Box{
-                                Top:    canvasBox.Bottom + DefaultXAxisMargin,
-                                Left:   cursor,
-                                Right:  cursor + bar.GetWidth() + sbc.GetBarSpacing(),
-                                Bottom: sbc.GetHeight(),
-                        }
-                        if len(bar.Name) &gt; 0 </span><span class="cov0" title="0">{
-                                Draw.TextWithin(r, bar.Name, barLabelBox, axisStyle)
-                        }</span>
-                        <span class="cov0" title="0">axisStyle.WriteToRenderer(r)
-                        r.MoveTo(barLabelBox.Right, canvasBox.Bottom)
-                        r.LineTo(barLabelBox.Right, canvasBox.Bottom+DefaultVerticalTickHeight)
-                        r.Stroke()
-                        cursor += bar.GetWidth() + sbc.GetBarSpacing()</span>
-                }
-        }
-}
-
-func (sbc StackedBarChart) drawYAxis(r Renderer, canvasBox Box) <span class="cov0" title="0">{
-        if sbc.YAxis.Show </span><span class="cov0" title="0">{
-                axisStyle := sbc.YAxis.InheritFrom(sbc.styleDefaultsAxes())
-                axisStyle.WriteToRenderer(r)
-                r.MoveTo(canvasBox.Right, canvasBox.Top)
-                r.LineTo(canvasBox.Right, canvasBox.Bottom)
-                r.Stroke()
-
-                r.MoveTo(canvasBox.Right, canvasBox.Bottom)
-                r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, canvasBox.Bottom)
-                r.Stroke()
-
-                ticks := seq.RangeWithStep(0.0, 1.0, 0.2)
-                for _, t := range ticks </span><span class="cov0" title="0">{
-                        axisStyle.GetStrokeOptions().WriteToRenderer(r)
-                        ty := canvasBox.Bottom - int(t*float64(canvasBox.Height()))
-                        r.MoveTo(canvasBox.Right, ty)
-                        r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, ty)
-                        r.Stroke()
-
-                        axisStyle.GetTextOptions().WriteToRenderer(r)
-                        text := fmt.Sprintf("%0.0f%%", t*100)
-
-                        tb := r.MeasureText(text)
-                        Draw.Text(r, text, canvasBox.Right+DefaultYAxisMargin+5, ty+(tb.Height()&gt;&gt;1), axisStyle)
-                }</span>
-
-        }
-}
-
-func (sbc StackedBarChart) drawTitle(r Renderer) <span class="cov0" title="0">{
-        if len(sbc.Title) &gt; 0 &amp;&amp; sbc.TitleStyle.Show </span><span class="cov0" title="0">{
-                r.SetFont(sbc.TitleStyle.GetFont(sbc.GetFont()))
-                r.SetFontColor(sbc.TitleStyle.GetFontColor(sbc.GetColorPalette().TextColor()))
-                titleFontSize := sbc.TitleStyle.GetFontSize(DefaultTitleFontSize)
-                r.SetFontSize(titleFontSize)
-
-                textBox := r.MeasureText(sbc.Title)
-
-                textWidth := textBox.Width()
-                textHeight := textBox.Height()
-
-                titleX := (sbc.GetWidth() &gt;&gt; 1) - (textWidth &gt;&gt; 1)
-                titleY := sbc.TitleStyle.Padding.GetTop(DefaultTitleTop) + textHeight
-
-                r.Text(sbc.Title, titleX, titleY)
-        }</span>
-}
-
-func (sbc StackedBarChart) getCanvasStyle() Style <span class="cov0" title="0">{
-        return sbc.Canvas.InheritFrom(sbc.styleDefaultsCanvas())
-}</span>
-
-func (sbc StackedBarChart) styleDefaultsCanvas() Style <span class="cov0" title="0">{
-        return Style{
-                FillColor:   sbc.GetColorPalette().CanvasColor(),
-                StrokeColor: sbc.GetColorPalette().CanvasStrokeColor(),
-                StrokeWidth: DefaultCanvasStrokeWidth,
-        }
-}</span>
-
-// GetColorPalette returns the color palette for the chart.
-func (sbc StackedBarChart) GetColorPalette() ColorPalette <span class="cov0" title="0">{
-        if sbc.ColorPalette != nil </span><span class="cov0" title="0">{
-                return sbc.ColorPalette
-        }</span>
-        <span class="cov0" title="0">return AlternateColorPalette</span>
-}
-
-func (sbc StackedBarChart) getDefaultCanvasBox() Box <span class="cov0" title="0">{
-        return sbc.Box()
-}</span>
-
-func (sbc StackedBarChart) getAdjustedCanvasBox(r Renderer, canvasBox Box) Box <span class="cov0" title="0">{
-        var totalWidth int
-        for _, bar := range sbc.Bars </span><span class="cov0" title="0">{
-                totalWidth += bar.GetWidth() + sbc.GetBarSpacing()
-        }</span>
-
-        <span class="cov0" title="0">if sbc.XAxis.Show </span><span class="cov0" title="0">{
-                xaxisHeight := DefaultVerticalTickHeight
-
-                axisStyle := sbc.XAxis.InheritFrom(sbc.styleDefaultsAxes())
-                axisStyle.WriteToRenderer(r)
-
-                cursor := canvasBox.Left
-                for _, bar := range sbc.Bars </span><span class="cov0" title="0">{
-                        if len(bar.Name) &gt; 0 </span><span class="cov0" title="0">{
-                                barLabelBox := Box{
-                                        Top:    canvasBox.Bottom + DefaultXAxisMargin,
-                                        Left:   cursor,
-                                        Right:  cursor + bar.GetWidth() + sbc.GetBarSpacing(),
-                                        Bottom: sbc.GetHeight(),
-                                }
-                                lines := Text.WrapFit(r, bar.Name, barLabelBox.Width(), axisStyle)
-                                linesBox := Text.MeasureLines(r, lines, axisStyle)
-
-                                xaxisHeight = util.Math.MaxInt(linesBox.Height()+(2*DefaultXAxisMargin), xaxisHeight)
-                        }</span>
-                }
-                <span class="cov0" title="0">return Box{
-                        Top:    canvasBox.Top,
-                        Left:   canvasBox.Left,
-                        Right:  canvasBox.Left + totalWidth,
-                        Bottom: sbc.GetHeight() - xaxisHeight,
-                }</span>
-        }
-        <span class="cov0" title="0">return Box{
-                Top:    canvasBox.Top,
-                Left:   canvasBox.Left,
-                Right:  canvasBox.Left + totalWidth,
-                Bottom: canvasBox.Bottom,
-        }</span>
-
-}
-
-// Box returns the chart bounds as a box.
-func (sbc StackedBarChart) Box() Box <span class="cov0" title="0">{
-        dpr := sbc.Background.Padding.GetRight(10)
-        dpb := sbc.Background.Padding.GetBottom(50)
-
-        return Box{
-                Top:    sbc.Background.Padding.GetTop(20),
-                Left:   sbc.Background.Padding.GetLeft(20),
-                Right:  sbc.GetWidth() - dpr,
-                Bottom: sbc.GetHeight() - dpb,
-        }
-}</span>
-
-func (sbc StackedBarChart) styleDefaultsStackedBarValue(index int) Style <span class="cov0" title="0">{
-        return Style{
-                StrokeColor: sbc.GetColorPalette().GetSeriesColor(index),
-                StrokeWidth: 3.0,
-                FillColor:   sbc.GetColorPalette().GetSeriesColor(index),
-        }
-}</span>
-
-func (sbc StackedBarChart) styleDefaultsTitle() Style <span class="cov0" title="0">{
-        return sbc.TitleStyle.InheritFrom(Style{
-                FontColor:           DefaultTextColor,
-                Font:                sbc.GetFont(),
-                FontSize:            sbc.getTitleFontSize(),
-                TextHorizontalAlign: TextHorizontalAlignCenter,
-                TextVerticalAlign:   TextVerticalAlignTop,
-                TextWrap:            TextWrapWord,
-        })
-}</span>
-
-func (sbc StackedBarChart) getTitleFontSize() float64 <span class="cov0" title="0">{
-        effectiveDimension := util.Math.MinInt(sbc.GetWidth(), sbc.GetHeight())
-        if effectiveDimension &gt;= 2048 </span><span class="cov0" title="0">{
-                return 48
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt;= 1024 </span><span class="cov0" title="0">{
-                return 24
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt;= 512 </span><span class="cov0" title="0">{
-                return 18
-        }</span> else<span class="cov0" title="0"> if effectiveDimension &gt;= 256 </span><span class="cov0" title="0">{
-                return 12
-        }</span>
-        <span class="cov0" title="0">return 10</span>
-}
-
-func (sbc StackedBarChart) styleDefaultsAxes() Style <span class="cov0" title="0">{
-        return Style{
-                StrokeColor:         DefaultAxisColor,
-                Font:                sbc.GetFont(),
-                FontSize:            DefaultAxisFontSize,
-                FontColor:           DefaultAxisColor,
-                TextHorizontalAlign: TextHorizontalAlignCenter,
-                TextVerticalAlign:   TextVerticalAlignTop,
-                TextWrap:            TextWrapWord,
-        }
-}</span>
-func (sbc StackedBarChart) styleDefaultsElements() Style <span class="cov0" title="0">{
-        return Style{
-                Font: sbc.GetFont(),
-        }
-}</span>
-</pre>
-		
-		<pre class="file" id="file57" style="display: none">package chart
-
-import (
-        "fmt"
-        "strings"
-
-        "github.com/golang/freetype/truetype"
-        "github.com/wcharczuk/go-chart/drawing"
-        "github.com/wcharczuk/go-chart/util"
-)
-
-const (
-        // Disabled indicates if the value should be interpreted as set intentionally to zero.
-        // this is because golang optionals aren't here yet.
-        Disabled = -1
-)
-
-// StyleShow is a prebuilt style with the `Show` property set to true.
-func StyleShow() Style <span class="cov8" title="1">{
-        return Style{
-                Show: true,
-        }
-}</span>
-
-// StyleTextDefaults returns a style for drawing outside a
-// chart context.
-func StyleTextDefaults() Style <span class="cov0" title="0">{
-        font, _ := GetDefaultFont()
-        return Style{
-                Show:      true,
-                Font:      font,
-                FontColor: DefaultTextColor,
-                FontSize:  DefaultTitleFontSize,
-        }
-}</span>
-
-// Style is a simple style set.
-type Style struct {
-        Show    bool
-        Padding Box
-
-        ClassName string
-
-        StrokeWidth     float64
-        StrokeColor     drawing.Color
-        StrokeDashArray []float64
-
-        DotColor drawing.Color
-        DotWidth float64
-
-        DotWidthProvider SizeProvider
-        DotColorProvider DotColorProvider
-
-        FillColor drawing.Color
-
-        FontSize  float64
-        FontColor drawing.Color
-        Font      *truetype.Font
-
-        TextHorizontalAlign TextHorizontalAlign
-        TextVerticalAlign   TextVerticalAlign
-        TextWrap            TextWrap
-        TextLineSpacing     int
-        TextRotationDegrees float64 //0 is unset or normal
-}
-
-// IsZero returns if the object is set or not.
-func (s Style) IsZero() bool <span class="cov8" title="1">{
-        return s.StrokeColor.IsZero() &amp;&amp;
-                s.StrokeWidth == 0 &amp;&amp;
-                s.DotColor.IsZero() &amp;&amp;
-                s.DotWidth == 0 &amp;&amp;
-                s.FillColor.IsZero() &amp;&amp;
-                s.FontColor.IsZero() &amp;&amp;
-                s.FontSize == 0 &amp;&amp;
-                s.Font == nil &amp;&amp;
-                s.ClassName == ""
-}</span>
-
-// String returns a text representation of the style.
-func (s Style) String() string <span class="cov0" title="0">{
-        if s.IsZero() </span><span class="cov0" title="0">{
-                return "{}"
-        }</span>
-
-        <span class="cov0" title="0">var output []string
-        if s.Show </span><span class="cov0" title="0">{
-                output = []string{"\"show\": true"}
-        }</span> else<span class="cov0" title="0"> {
-                output = []string{"\"show\": false"}
-        }</span>
-
-        <span class="cov0" title="0">if s.ClassName != "" </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"class_name\": %s", s.ClassName))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"class_name\": null")
-        }</span>
-
-        <span class="cov0" title="0">if !s.Padding.IsZero() </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"padding\": %s", s.Padding.String()))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"padding\": null")
-        }</span>
-
-        <span class="cov0" title="0">if s.StrokeWidth &gt;= 0 </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"stroke_width\": %0.2f", s.StrokeWidth))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"stroke_width\": null")
-        }</span>
-
-        <span class="cov0" title="0">if !s.StrokeColor.IsZero() </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"stroke_color\": %s", s.StrokeColor.String()))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"stroke_color\": null")
-        }</span>
-
-        <span class="cov0" title="0">if len(s.StrokeDashArray) &gt; 0 </span><span class="cov0" title="0">{
-                var elements []string
-                for _, v := range s.StrokeDashArray </span><span class="cov0" title="0">{
-                        elements = append(elements, fmt.Sprintf("%.2f", v))
-                }</span>
-                <span class="cov0" title="0">dashArray := strings.Join(elements, ", ")
-                output = append(output, fmt.Sprintf("\"stroke_dash_array\": [%s]", dashArray))</span>
-        } else<span class="cov0" title="0"> {
-                output = append(output, "\"stroke_dash_array\": null")
-        }</span>
-
-        <span class="cov0" title="0">if s.DotWidth &gt;= 0 </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"dot_width\": %0.2f", s.DotWidth))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"dot_width\": null")
-        }</span>
-
-        <span class="cov0" title="0">if !s.DotColor.IsZero() </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"dot_color\": %s", s.DotColor.String()))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"dot_color\": null")
-        }</span>
-
-        <span class="cov0" title="0">if !s.FillColor.IsZero() </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"fill_color\": %s", s.FillColor.String()))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"fill_color\": null")
-        }</span>
-
-        <span class="cov0" title="0">if s.FontSize != 0 </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"font_size\": \"%0.2fpt\"", s.FontSize))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"font_size\": null")
-        }</span>
-
-        <span class="cov0" title="0">if !s.FontColor.IsZero() </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"font_color\": %s", s.FontColor.String()))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"font_color\": null")
-        }</span>
-
-        <span class="cov0" title="0">if s.Font != nil </span><span class="cov0" title="0">{
-                output = append(output, fmt.Sprintf("\"font\": \"%s\"", s.Font.Name(truetype.NameIDFontFamily)))
-        }</span> else<span class="cov0" title="0"> {
-                output = append(output, "\"font_color\": null")
-        }</span>
-
-        <span class="cov0" title="0">return "{" + strings.Join(output, ", ") + "}"</span>
-}
-
-func (s Style) GetClassName(defaults ...string) string <span class="cov8" title="1">{
-        if s.ClassName == "" </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return ""</span>
-        }
-        <span class="cov0" title="0">return s.ClassName</span>
-}
-
-// GetStrokeColor returns the stroke color.
-func (s Style) GetStrokeColor(defaults ...drawing.Color) drawing.Color <span class="cov8" title="1">{
-        if s.StrokeColor.IsZero() </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return drawing.ColorTransparent</span>
-        }
-        <span class="cov8" title="1">return s.StrokeColor</span>
-}
-
-// GetFillColor returns the fill color.
-func (s Style) GetFillColor(defaults ...drawing.Color) drawing.Color <span class="cov8" title="1">{
-        if s.FillColor.IsZero() </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return drawing.ColorTransparent</span>
-        }
-        <span class="cov8" title="1">return s.FillColor</span>
-}
-
-// GetDotColor returns the stroke color.
-func (s Style) GetDotColor(defaults ...drawing.Color) drawing.Color <span class="cov8" title="1">{
-        if s.DotColor.IsZero() </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return drawing.ColorTransparent</span>
-        }
-        <span class="cov0" title="0">return s.DotColor</span>
-}
-
-// GetStrokeWidth returns the stroke width.
-func (s Style) GetStrokeWidth(defaults ...float64) float64 <span class="cov8" title="1">{
-        if s.StrokeWidth == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return DefaultStrokeWidth</span>
-        }
-        <span class="cov8" title="1">return s.StrokeWidth</span>
-}
-
-// GetDotWidth returns the dot width for scatter plots.
-func (s Style) GetDotWidth(defaults ...float64) float64 <span class="cov8" title="1">{
-        if s.DotWidth == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return DefaultDotWidth</span>
-        }
-        <span class="cov0" title="0">return s.DotWidth</span>
-}
-
-// GetStrokeDashArray returns the stroke dash array.
-func (s Style) GetStrokeDashArray(defaults ...[]float64) []float64 <span class="cov8" title="1">{
-        if len(s.StrokeDashArray) == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return nil</span>
-        }
-        <span class="cov0" title="0">return s.StrokeDashArray</span>
-}
-
-// GetFontSize gets the font size.
-func (s Style) GetFontSize(defaults ...float64) float64 <span class="cov8" title="1">{
-        if s.FontSize == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return DefaultFontSize</span>
-        }
-        <span class="cov8" title="1">return s.FontSize</span>
-}
-
-// GetFontColor gets the font size.
-func (s Style) GetFontColor(defaults ...drawing.Color) drawing.Color <span class="cov8" title="1">{
-        if s.FontColor.IsZero() </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return drawing.ColorTransparent</span>
-        }
-        <span class="cov8" title="1">return s.FontColor</span>
-}
-
-// GetFont returns the font face.
-func (s Style) GetFont(defaults ...*truetype.Font) *truetype.Font <span class="cov8" title="1">{
-        if s.Font == nil </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return nil</span>
-        }
-        <span class="cov8" title="1">return s.Font</span>
-}
-
-// GetPadding returns the padding.
-func (s Style) GetPadding(defaults ...Box) Box <span class="cov8" title="1">{
-        if s.Padding.IsZero() </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return Box{}</span>
-        }
-        <span class="cov8" title="1">return s.Padding</span>
-}
-
-// GetTextHorizontalAlign returns the horizontal alignment.
-func (s Style) GetTextHorizontalAlign(defaults ...TextHorizontalAlign) TextHorizontalAlign <span class="cov8" title="1">{
-        if s.TextHorizontalAlign == TextHorizontalAlignUnset </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return TextHorizontalAlignUnset</span>
-        }
-        <span class="cov8" title="1">return s.TextHorizontalAlign</span>
-}
-
-// GetTextVerticalAlign returns the vertical alignment.
-func (s Style) GetTextVerticalAlign(defaults ...TextVerticalAlign) TextVerticalAlign <span class="cov8" title="1">{
-        if s.TextVerticalAlign == TextVerticalAlignUnset </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return TextVerticalAlignUnset</span>
-        }
-        <span class="cov8" title="1">return s.TextVerticalAlign</span>
-}
-
-// GetTextWrap returns the word wrap.
-func (s Style) GetTextWrap(defaults ...TextWrap) TextWrap <span class="cov8" title="1">{
-        if s.TextWrap == TextWrapUnset </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov0" title="0">return TextWrapUnset</span>
-        }
-        <span class="cov0" title="0">return s.TextWrap</span>
-}
-
-// GetTextLineSpacing returns the spacing in pixels between lines of text (vertically).
-func (s Style) GetTextLineSpacing(defaults ...int) int <span class="cov8" title="1">{
-        if s.TextLineSpacing == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return DefaultLineSpacing</span>
-        }
-        <span class="cov0" title="0">return s.TextLineSpacing</span>
-}
-
-// GetTextRotationDegrees returns the text rotation in degrees.
-func (s Style) GetTextRotationDegrees(defaults ...float64) float64 <span class="cov8" title="1">{
-        if s.TextRotationDegrees == 0 </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov8" title="1">{
-                        return defaults[0]
-                }</span>
-        }
-        <span class="cov8" title="1">return s.TextRotationDegrees</span>
-}
-
-// WriteToRenderer passes the style's options to a renderer.
-func (s Style) WriteToRenderer(r Renderer) <span class="cov8" title="1">{
-        r.SetClassName(s.GetClassName())
-        r.SetStrokeColor(s.GetStrokeColor())
-        r.SetStrokeWidth(s.GetStrokeWidth())
-        r.SetStrokeDashArray(s.GetStrokeDashArray())
-        r.SetFillColor(s.GetFillColor())
-        r.SetFont(s.GetFont())
-        r.SetFontColor(s.GetFontColor())
-        r.SetFontSize(s.GetFontSize())
-
-        r.ClearTextRotation()
-        if s.GetTextRotationDegrees() != 0 </span><span class="cov0" title="0">{
-                r.SetTextRotation(util.Math.DegreesToRadians(s.GetTextRotationDegrees()))
-        }</span>
-}
-
-// WriteDrawingOptionsToRenderer passes just the drawing style options to a renderer.
-func (s Style) WriteDrawingOptionsToRenderer(r Renderer) <span class="cov8" title="1">{
-        r.SetClassName(s.GetClassName())
-        r.SetStrokeColor(s.GetStrokeColor())
-        r.SetStrokeWidth(s.GetStrokeWidth())
-        r.SetStrokeDashArray(s.GetStrokeDashArray())
-        r.SetFillColor(s.GetFillColor())
-}</span>
-
-// WriteTextOptionsToRenderer passes just the text style options to a renderer.
-func (s Style) WriteTextOptionsToRenderer(r Renderer) <span class="cov8" title="1">{
-        r.SetClassName(s.GetClassName())
-        r.SetFont(s.GetFont())
-        r.SetFontColor(s.GetFontColor())
-        r.SetFontSize(s.GetFontSize())
-}</span>
-
-// InheritFrom coalesces two styles into a new style.
-func (s Style) InheritFrom(defaults Style) (final Style) <span class="cov8" title="1">{
-        final.ClassName = s.GetClassName(defaults.ClassName)
-
-        final.StrokeColor = s.GetStrokeColor(defaults.StrokeColor)
-        final.StrokeWidth = s.GetStrokeWidth(defaults.StrokeWidth)
-        final.StrokeDashArray = s.GetStrokeDashArray(defaults.StrokeDashArray)
-
-        final.DotColor = s.GetDotColor(defaults.DotColor)
-        final.DotWidth = s.GetDotWidth(defaults.DotWidth)
-
-        final.DotWidthProvider = s.DotWidthProvider
-        final.DotColorProvider = s.DotColorProvider
-
-        final.FillColor = s.GetFillColor(defaults.FillColor)
-        final.FontColor = s.GetFontColor(defaults.FontColor)
-        final.FontSize = s.GetFontSize(defaults.FontSize)
-        final.Font = s.GetFont(defaults.Font)
-        final.Padding = s.GetPadding(defaults.Padding)
-        final.TextHorizontalAlign = s.GetTextHorizontalAlign(defaults.TextHorizontalAlign)
-        final.TextVerticalAlign = s.GetTextVerticalAlign(defaults.TextVerticalAlign)
-        final.TextWrap = s.GetTextWrap(defaults.TextWrap)
-        final.TextLineSpacing = s.GetTextLineSpacing(defaults.TextLineSpacing)
-        final.TextRotationDegrees = s.GetTextRotationDegrees(defaults.TextRotationDegrees)
-
-        return
-}</span>
-
-// GetStrokeOptions returns the stroke components.
-func (s Style) GetStrokeOptions() Style <span class="cov8" title="1">{
-        return Style{
-                ClassName:       s.ClassName,
-                StrokeDashArray: s.StrokeDashArray,
-                StrokeColor:     s.StrokeColor,
-                StrokeWidth:     s.StrokeWidth,
-        }
-}</span>
-
-// GetFillOptions returns the fill components.
-func (s Style) GetFillOptions() Style <span class="cov8" title="1">{
-        return Style{
-                ClassName: s.ClassName,
-                FillColor: s.FillColor,
-        }
-}</span>
-
-// GetDotOptions returns the dot components.
-func (s Style) GetDotOptions() Style <span class="cov0" title="0">{
-        return Style{
-                ClassName:       s.ClassName,
-                StrokeDashArray: nil,
-                FillColor:       s.DotColor,
-                StrokeColor:     s.DotColor,
-                StrokeWidth:     1.0,
-        }
-}</span>
-
-// GetFillAndStrokeOptions returns the fill and stroke components.
-func (s Style) GetFillAndStrokeOptions() Style <span class="cov8" title="1">{
-        return Style{
-                ClassName:       s.ClassName,
-                StrokeDashArray: s.StrokeDashArray,
-                FillColor:       s.FillColor,
-                StrokeColor:     s.StrokeColor,
-                StrokeWidth:     s.StrokeWidth,
-        }
-}</span>
-
-// GetTextOptions returns just the text components of the style.
-func (s Style) GetTextOptions() Style <span class="cov8" title="1">{
-        return Style{
-                ClassName:           s.ClassName,
-                FontColor:           s.FontColor,
-                FontSize:            s.FontSize,
-                Font:                s.Font,
-                TextHorizontalAlign: s.TextHorizontalAlign,
-                TextVerticalAlign:   s.TextVerticalAlign,
-                TextWrap:            s.TextWrap,
-                TextLineSpacing:     s.TextLineSpacing,
-                TextRotationDegrees: s.TextRotationDegrees,
-        }
-}</span>
-
-// ShouldDrawStroke tells drawing functions if they should draw the stroke.
-func (s Style) ShouldDrawStroke() bool <span class="cov8" title="1">{
-        return !s.StrokeColor.IsZero() &amp;&amp; s.StrokeWidth &gt; 0
-}</span>
-
-// ShouldDrawDot tells drawing functions if they should draw the dot.
-func (s Style) ShouldDrawDot() bool <span class="cov8" title="1">{
-        return (!s.DotColor.IsZero() &amp;&amp; s.DotWidth &gt; 0) || s.DotColorProvider != nil || s.DotWidthProvider != nil
-}</span>
-
-// ShouldDrawFill tells drawing functions if they should draw the stroke.
-func (s Style) ShouldDrawFill() bool <span class="cov8" title="1">{
-        return !s.FillColor.IsZero()
-}</span>
-</pre>
-		
-		<pre class="file" id="file58" style="display: none">package chart
-
-import (
-        "strings"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// TextHorizontalAlign is an enum for the horizontal alignment options.
-type TextHorizontalAlign int
-
-const (
-        // TextHorizontalAlignUnset is the unset state for text horizontal alignment.
-        TextHorizontalAlignUnset TextHorizontalAlign = 0
-        // TextHorizontalAlignLeft aligns a string horizontally so that it's left ligature starts at horizontal pixel 0.
-        TextHorizontalAlignLeft TextHorizontalAlign = 1
-        // TextHorizontalAlignCenter left aligns a string horizontally so that there are equal pixels
-        // to the left and to the right of a string within a box.
-        TextHorizontalAlignCenter TextHorizontalAlign = 2
-        // TextHorizontalAlignRight right aligns a string horizontally so that the right ligature ends at the right-most pixel
-        // of a box.
-        TextHorizontalAlignRight TextHorizontalAlign = 3
-)
-
-// TextWrap is an enum for the word wrap options.
-type TextWrap int
-
-const (
-        // TextWrapUnset is the unset state for text wrap options.
-        TextWrapUnset TextWrap = 0
-        // TextWrapNone will spill text past horizontal boundaries.
-        TextWrapNone TextWrap = 1
-        // TextWrapWord will split a string on words (i.e. spaces) to fit within a horizontal boundary.
-        TextWrapWord TextWrap = 2
-        // TextWrapRune will split a string on a rune (i.e. utf-8 codepage) to fit within a horizontal boundary.
-        TextWrapRune TextWrap = 3
-)
-
-// TextVerticalAlign is an enum for the vertical alignment options.
-type TextVerticalAlign int
-
-const (
-        // TextVerticalAlignUnset is the unset state for vertical alignment options.
-        TextVerticalAlignUnset TextVerticalAlign = 0
-        // TextVerticalAlignBaseline aligns text according to the "baseline" of the string, or where a normal ascender begins.
-        TextVerticalAlignBaseline TextVerticalAlign = 1
-        // TextVerticalAlignBottom aligns the text according to the lowers pixel of any of the ligatures (ex. g or q both extend below the baseline).
-        TextVerticalAlignBottom TextVerticalAlign = 2
-        // TextVerticalAlignMiddle aligns the text so that there is an equal amount of space above and below the top and bottom of the ligatures.
-        TextVerticalAlignMiddle TextVerticalAlign = 3
-        // TextVerticalAlignMiddleBaseline aligns the text veritcally so that there is an equal number of pixels above and below the baseline of the string.
-        TextVerticalAlignMiddleBaseline TextVerticalAlign = 4
-        // TextVerticalAlignTop alignts the text so that the top of the ligatures are at y-pixel 0 in the container.
-        TextVerticalAlignTop TextVerticalAlign = 5
-)
-
-var (
-        // Text contains utilities for text.
-        Text = &amp;text{}
-)
-
-// TextStyle encapsulates text style options.
-type TextStyle struct {
-        HorizontalAlign TextHorizontalAlign
-        VerticalAlign   TextVerticalAlign
-        Wrap            TextWrap
-}
-
-type text struct{}
-
-func (t text) WrapFit(r Renderer, value string, width int, style Style) []string <span class="cov8" title="1">{
-        switch style.TextWrap </span>{
-        case TextWrapRune:<span class="cov0" title="0">
-                return t.WrapFitRune(r, value, width, style)</span>
-        case TextWrapWord:<span class="cov8" title="1">
-                return t.WrapFitWord(r, value, width, style)</span>
-        }
-        <span class="cov0" title="0">return []string{value}</span>
-}
-
-func (t text) WrapFitWord(r Renderer, value string, width int, style Style) []string <span class="cov8" title="1">{
-        style.WriteToRenderer(r)
-
-        var output []string
-        var line string
-        var word string
-
-        var textBox Box
-
-        for _, c := range value </span><span class="cov8" title="1">{
-                if c == rune('\n') </span><span class="cov8" title="1">{ // commit the line to output
-                        output = append(output, t.Trim(line+word))
-                        line = ""
-                        word = ""
-                        continue</span>
-                }
-
-                <span class="cov8" title="1">textBox = r.MeasureText(line + word + string(c))
-
-                if textBox.Width() &gt;= width </span><span class="cov8" title="1">{
-                        output = append(output, t.Trim(line))
-                        line = word
-                        word = string(c)
-                        continue</span>
-                }
-
-                <span class="cov8" title="1">if c == rune(' ') || c == rune('\t') </span><span class="cov8" title="1">{
-                        line = line + word + string(c)
-                        word = ""
-                        continue</span>
-                }
-                <span class="cov8" title="1">word = word + string(c)</span>
-        }
-
-        <span class="cov8" title="1">return append(output, t.Trim(line+word))</span>
-}
-
-func (t text) WrapFitRune(r Renderer, value string, width int, style Style) []string <span class="cov8" title="1">{
-        style.WriteToRenderer(r)
-
-        var output []string
-        var line string
-        var textBox Box
-        for _, c := range value </span><span class="cov8" title="1">{
-                if c == rune('\n') </span><span class="cov0" title="0">{
-                        output = append(output, line)
-                        line = ""
-                        continue</span>
-                }
-
-                <span class="cov8" title="1">textBox = r.MeasureText(line + string(c))
-
-                if textBox.Width() &gt;= width </span><span class="cov8" title="1">{
-                        output = append(output, line)
-                        line = string(c)
-                        continue</span>
-                }
-                <span class="cov8" title="1">line = line + string(c)</span>
-        }
-        <span class="cov8" title="1">return t.appendLast(output, line)</span>
-}
-
-func (t text) Trim(value string) string <span class="cov8" title="1">{
-        return strings.Trim(value, " \t\n\r")
-}</span>
-
-func (t text) MeasureLines(r Renderer, lines []string, style Style) Box <span class="cov8" title="1">{
-        style.WriteTextOptionsToRenderer(r)
-        var output Box
-        for index, line := range lines </span><span class="cov8" title="1">{
-                lineBox := r.MeasureText(line)
-                output.Right = util.Math.MaxInt(lineBox.Right, output.Right)
-                output.Bottom += lineBox.Height()
-                if index &lt; len(lines)-1 </span><span class="cov0" title="0">{
-                        output.Bottom += +style.GetTextLineSpacing()
-                }</span>
-        }
-        <span class="cov8" title="1">return output</span>
-}
-
-func (t text) appendLast(lines []string, text string) []string <span class="cov8" title="1">{
-        if len(lines) == 0 </span><span class="cov0" title="0">{
-                return []string{text}
-        }</span>
-        <span class="cov8" title="1">lastLine := lines[len(lines)-1]
-        lines[len(lines)-1] = lastLine + text
-        return lines</span>
-}
-</pre>
-		
-		<pre class="file" id="file59" style="display: none">package chart
-
-import (
-        "fmt"
-        "math"
-        "strings"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// TicksProvider is a type that provides ticks.
-type TicksProvider interface {
-        GetTicks(r Renderer, defaults Style, vf ValueFormatter) []Tick
-}
-
-// Tick represents a label on an axis.
-type Tick struct {
-        Value float64
-        Label string
-}
-
-// Ticks is an array of ticks.
-type Ticks []Tick
-
-// Len returns the length of the ticks set.
-func (t Ticks) Len() int <span class="cov0" title="0">{
-        return len(t)
-}</span>
-
-// Swap swaps two elements.
-func (t Ticks) Swap(i, j int) <span class="cov0" title="0">{
-        t[i], t[j] = t[j], t[i]
-}</span>
-
-// Less returns if i's value is less than j's value.
-func (t Ticks) Less(i, j int) bool <span class="cov0" title="0">{
-        return t[i].Value &lt; t[j].Value
-}</span>
-
-// String returns a string representation of the set of ticks.
-func (t Ticks) String() string <span class="cov0" title="0">{
-        var values []string
-        for i, tick := range t </span><span class="cov0" title="0">{
-                values = append(values, fmt.Sprintf("[%d: %s]", i, tick.Label))
-        }</span>
-        <span class="cov0" title="0">return strings.Join(values, ", ")</span>
-}
-
-// GenerateContinuousTicks generates a set of ticks.
-func GenerateContinuousTicks(r Renderer, ra Range, isVertical bool, style Style, vf ValueFormatter) []Tick <span class="cov8" title="1">{
-        if vf == nil </span><span class="cov0" title="0">{
-                vf = FloatValueFormatter
-        }</span>
-
-        <span class="cov8" title="1">var ticks []Tick
-        min, max := ra.GetMin(), ra.GetMax()
-
-        if ra.IsDescending() </span><span class="cov8" title="1">{
-                ticks = append(ticks, Tick{
-                        Value: max,
-                        Label: vf(max),
-                })
-        }</span> else<span class="cov8" title="1"> {
-                ticks = append(ticks, Tick{
-                        Value: min,
-                        Label: vf(min),
-                })
-        }</span>
-
-        <span class="cov8" title="1">minLabel := vf(min)
-        style.GetTextOptions().WriteToRenderer(r)
-        labelBox := r.MeasureText(minLabel)
-
-        var tickSize float64
-        if isVertical </span><span class="cov8" title="1">{
-                tickSize = float64(labelBox.Height() + DefaultMinimumTickVerticalSpacing)
-        }</span> else<span class="cov8" title="1"> {
-                tickSize = float64(labelBox.Width() + DefaultMinimumTickHorizontalSpacing)
-        }</span>
-
-        <span class="cov8" title="1">domain := float64(ra.GetDomain())
-        domainRemainder := domain - (tickSize * 2)
-        intermediateTickCount := int(math.Floor(float64(domainRemainder) / float64(tickSize)))
-
-        rangeDelta := math.Abs(max - min)
-        tickStep := rangeDelta / float64(intermediateTickCount)
-
-        roundTo := util.Math.GetRoundToForDelta(rangeDelta) / 10
-        intermediateTickCount = util.Math.MinInt(intermediateTickCount, DefaultTickCountSanityCheck)
-
-        for x := 1; x &lt; intermediateTickCount; x++ </span><span class="cov8" title="1">{
-                var tickValue float64
-                if ra.IsDescending() </span><span class="cov8" title="1">{
-                        tickValue = max - util.Math.RoundUp(tickStep*float64(x), roundTo)
-                }</span> else<span class="cov8" title="1"> {
-                        tickValue = min + util.Math.RoundUp(tickStep*float64(x), roundTo)
-                }</span>
-                <span class="cov8" title="1">ticks = append(ticks, Tick{
-                        Value: tickValue,
-                        Label: vf(tickValue),
-                })</span>
-        }
-
-        <span class="cov8" title="1">if ra.IsDescending() </span><span class="cov8" title="1">{
-                ticks = append(ticks, Tick{
-                        Value: min,
-                        Label: vf(min),
-                })
-        }</span> else<span class="cov8" title="1"> {
-                ticks = append(ticks, Tick{
-                        Value: max,
-                        Label: vf(max),
-                })
-        }</span>
-
-        <span class="cov8" title="1">return ticks</span>
-}
-</pre>
-		
-		<pre class="file" id="file60" style="display: none">package chart
-
-import (
-        "fmt"
-        "time"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// Interface Assertions.
-var (
-        _ Series                 = (*TimeSeries)(nil)
-        _ FirstValuesProvider    = (*TimeSeries)(nil)
-        _ LastValuesProvider     = (*TimeSeries)(nil)
-        _ ValueFormatterProvider = (*TimeSeries)(nil)
-)
-
-// TimeSeries is a line on a chart.
-type TimeSeries struct {
-        Name  string
-        Style Style
-
-        YAxis YAxisType
-
-        XValues []time.Time
-        YValues []float64
-}
-
-// GetName returns the name of the time series.
-func (ts TimeSeries) GetName() string <span class="cov0" title="0">{
-        return ts.Name
-}</span>
-
-// GetStyle returns the line style.
-func (ts TimeSeries) GetStyle() Style <span class="cov8" title="1">{
-        return ts.Style
-}</span>
-
-// Len returns the number of elements in the series.
-func (ts TimeSeries) Len() int <span class="cov8" title="1">{
-        return len(ts.XValues)
-}</span>
-
-// GetValues gets x, y values at a given index.
-func (ts TimeSeries) GetValues(index int) (x, y float64) <span class="cov8" title="1">{
-        x = util.Time.ToFloat64(ts.XValues[index])
-        y = ts.YValues[index]
-        return
-}</span>
-
-// GetFirstValues gets the first values.
-func (ts TimeSeries) GetFirstValues() (x, y float64) <span class="cov0" title="0">{
-        x = util.Time.ToFloat64(ts.XValues[0])
-        y = ts.YValues[0]
-        return
-}</span>
-
-// GetLastValues gets the last values.
-func (ts TimeSeries) GetLastValues() (x, y float64) <span class="cov0" title="0">{
-        x = util.Time.ToFloat64(ts.XValues[len(ts.XValues)-1])
-        y = ts.YValues[len(ts.YValues)-1]
-        return
-}</span>
-
-// GetValueFormatters returns value formatter defaults for the series.
-func (ts TimeSeries) GetValueFormatters() (x, y ValueFormatter) <span class="cov8" title="1">{
-        x = TimeValueFormatter
-        y = FloatValueFormatter
-        return
-}</span>
-
-// GetYAxis returns which YAxis the series draws on.
-func (ts TimeSeries) GetYAxis() YAxisType <span class="cov8" title="1">{
-        return ts.YAxis
-}</span>
-
-// Render renders the series.
-func (ts TimeSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) <span class="cov8" title="1">{
-        style := ts.Style.InheritFrom(defaults)
-        Draw.LineSeries(r, canvasBox, xrange, yrange, style, ts)
-}</span>
-
-// Validate validates the series.
-func (ts TimeSeries) Validate() error <span class="cov8" title="1">{
-        if len(ts.XValues) == 0 </span><span class="cov8" title="1">{
-                return fmt.Errorf("time series must have xvalues set")
-        }</span>
-
-        <span class="cov8" title="1">if len(ts.YValues) == 0 </span><span class="cov8" title="1">{
-                return fmt.Errorf("time series must have yvalues set")
-        }</span>
-        <span class="cov8" title="1">return nil</span>
-}
-</pre>
-		
-		<pre class="file" id="file61" style="display: none">package util
-
-import (
-        "time"
-)
-
-const (
-        // AllDaysMask is a bitmask of all the days of the week.
-        AllDaysMask = 1&lt;&lt;uint(time.Sunday) | 1&lt;&lt;uint(time.Monday) | 1&lt;&lt;uint(time.Tuesday) | 1&lt;&lt;uint(time.Wednesday) | 1&lt;&lt;uint(time.Thursday) | 1&lt;&lt;uint(time.Friday) | 1&lt;&lt;uint(time.Saturday)
-        // WeekDaysMask is a bitmask of all the weekdays of the week.
-        WeekDaysMask = 1&lt;&lt;uint(time.Monday) | 1&lt;&lt;uint(time.Tuesday) | 1&lt;&lt;uint(time.Wednesday) | 1&lt;&lt;uint(time.Thursday) | 1&lt;&lt;uint(time.Friday)
-        //WeekendDaysMask is a bitmask of the weekend days of the week.
-        WeekendDaysMask = 1&lt;&lt;uint(time.Sunday) | 1&lt;&lt;uint(time.Saturday)
-)
-
-var (
-        // DaysOfWeek are all the time.Weekday in an array for utility purposes.
-        DaysOfWeek = []time.Weekday{
-                time.Sunday,
-                time.Monday,
-                time.Tuesday,
-                time.Wednesday,
-                time.Thursday,
-                time.Friday,
-                time.Saturday,
-        }
-
-        // WeekDays are the business time.Weekday in an array.
-        WeekDays = []time.Weekday{
-                time.Monday,
-                time.Tuesday,
-                time.Wednesday,
-                time.Thursday,
-                time.Friday,
-        }
-
-        // WeekendDays are the weekend time.Weekday in an array.
-        WeekendDays = []time.Weekday{
-                time.Sunday,
-                time.Saturday,
-        }
-
-        //Epoch is unix epoc saved for utility purposes.
-        Epoch = time.Unix(0, 0)
-)
-
-// Date contains utility functions that operate on dates.
-var Date date
-
-type date struct{}
-
-func (d date) MustEastern() *time.Location <span class="cov8" title="1">{
-        if eastern, err := d.Eastern(); err != nil </span><span class="cov0" title="0">{
-                panic(err)</span>
-        } else<span class="cov8" title="1"> {
-                return eastern
-        }</span>
-}
-
-// Eastern returns the eastern timezone.
-func (d date) Eastern() (*time.Location, error) <span class="cov8" title="1">{
-        // Try POSIX
-        est, err := time.LoadLocation("America/New_York")
-        if err != nil </span><span class="cov0" title="0">{
-                // Try Windows
-                est, err = time.LoadLocation("EST")
-                if err != nil </span><span class="cov0" title="0">{
-                        return nil, err
-                }</span>
-        }
-        <span class="cov8" title="1">return est, nil</span>
-}
-
-func (d date) MustPacific() *time.Location <span class="cov0" title="0">{
-        if pst, err := d.Pacific(); err != nil </span><span class="cov0" title="0">{
-                panic(err)</span>
-        } else<span class="cov0" title="0"> {
-                return pst
-        }</span>
-}
-
-// Pacific returns the pacific timezone.
-func (d date) Pacific() (*time.Location, error) <span class="cov0" title="0">{
-        // Try POSIX
-        pst, err := time.LoadLocation("America/Los_Angeles")
-        if err != nil </span><span class="cov0" title="0">{
-                // Try Windows
-                pst, err = time.LoadLocation("PST")
-                if err != nil </span><span class="cov0" title="0">{
-                        return nil, err
-                }</span>
-        }
-        <span class="cov0" title="0">return pst, nil</span>
-}
-
-// TimeUTC returns a new time.Time for the given clock components in UTC.
-// It is meant to be used with the `OnDate` function.
-func (d date) TimeUTC(hour, min, sec, nsec int) time.Time <span class="cov0" title="0">{
-        return time.Date(0, 0, 0, hour, min, sec, nsec, time.UTC)
-}</span>
-
-// Time returns a new time.Time for the given clock components.
-// It is meant to be used with the `OnDate` function.
-func (d date) Time(hour, min, sec, nsec int, loc *time.Location) time.Time <span class="cov8" title="1">{
-        return time.Date(0, 0, 0, hour, min, sec, nsec, loc)
-}</span>
-
-// DateUTC returns a new time.Time for the given date comonents at (noon) in UTC.
-func (d date) DateUTC(year, month, day int) time.Time <span class="cov0" title="0">{
-        return time.Date(year, time.Month(month), day, 12, 0, 0, 0, time.UTC)
-}</span>
-
-// DateUTC returns a new time.Time for the given date comonents at (noon) in a given location.
-func (d date) Date(year, month, day int, loc *time.Location) time.Time <span class="cov8" title="1">{
-        return time.Date(year, time.Month(month), day, 12, 0, 0, 0, loc)
-}</span>
-
-// OnDate returns the clock components of clock (hour,minute,second) on the date components of d.
-func (d date) OnDate(clock, date time.Time) time.Time <span class="cov8" title="1">{
-        tzAdjusted := date.In(clock.Location())
-        return time.Date(tzAdjusted.Year(), tzAdjusted.Month(), tzAdjusted.Day(), clock.Hour(), clock.Minute(), clock.Second(), clock.Nanosecond(), clock.Location())
-}</span>
-
-// NoonOnDate is a shortcut for On(Time(12,0,0), cd) a.k.a. noon on a given date.
-func (d date) NoonOnDate(cd time.Time) time.Time <span class="cov8" title="1">{
-        return time.Date(cd.Year(), cd.Month(), cd.Day(), 12, 0, 0, 0, cd.Location())
-}</span>
-
-// IsWeekDay returns if the day is a monday-&gt;friday.
-func (d date) IsWeekDay(day time.Weekday) bool <span class="cov0" title="0">{
-        return !d.IsWeekendDay(day)
-}</span>
-
-// IsWeekendDay returns if the day is a monday-&gt;friday.
-func (d date) IsWeekendDay(day time.Weekday) bool <span class="cov0" title="0">{
-        return day == time.Saturday || day == time.Sunday
-}</span>
-
-// Before returns if a timestamp is strictly before another date (ignoring hours, minutes etc.)
-func (d date) Before(before, reference time.Time) bool <span class="cov8" title="1">{
-        tzAdjustedBefore := before.In(reference.Location())
-        if tzAdjustedBefore.Year() &lt; reference.Year() </span><span class="cov8" title="1">{
-                return true
-        }</span>
-        <span class="cov8" title="1">if tzAdjustedBefore.Month() &lt; reference.Month() </span><span class="cov8" title="1">{
-                return true
-        }</span>
-        <span class="cov8" title="1">return tzAdjustedBefore.Year() == reference.Year() &amp;&amp; tzAdjustedBefore.Month() == reference.Month() &amp;&amp; tzAdjustedBefore.Day() &lt; reference.Day()</span>
-}
-
-const (
-        _secondsPerHour = 60 * 60
-        _secondsPerDay  = 60 * 60 * 24
-)
-
-// NextDay returns the timestamp advanced a day.
-func (d date) NextDay(ts time.Time) time.Time <span class="cov0" title="0">{
-        return ts.AddDate(0, 0, 1)
-}</span>
-
-// NextHour returns the next timestamp on the hour.
-func (d date) NextHour(ts time.Time) time.Time <span class="cov8" title="1">{
-        //advance a full hour ...
-        advanced := ts.Add(time.Hour)
-        minutes := time.Duration(advanced.Minute()) * time.Minute
-        final := advanced.Add(-minutes)
-        return time.Date(final.Year(), final.Month(), final.Day(), final.Hour(), 0, 0, 0, final.Location())
-}</span>
-
-// NextDayOfWeek returns the next instance of a given weekday after a given timestamp.
-func (d date) NextDayOfWeek(after time.Time, dayOfWeek time.Weekday) time.Time <span class="cov8" title="1">{
-        afterWeekday := after.Weekday()
-        if afterWeekday == dayOfWeek </span><span class="cov8" title="1">{
-                return after.AddDate(0, 0, 7)
-        }</span>
-
-        // 1 vs 5 ~ add 4 days
-        <span class="cov8" title="1">if afterWeekday &lt; dayOfWeek </span><span class="cov8" title="1">{
-                dayDelta := int(dayOfWeek - afterWeekday)
-                return after.AddDate(0, 0, dayDelta)
-        }</span>
-
-        // 5 vs 1, add 7-(5-1) ~ 3 days
-        <span class="cov8" title="1">dayDelta := 7 - int(afterWeekday-dayOfWeek)
-        return after.AddDate(0, 0, dayDelta)</span>
-}
-</pre>
-		
-		<pre class="file" id="file62" style="display: none">package util
-
-import (
-        "bufio"
-        "io"
-        "os"
-)
-
-var (
-        // File contains file utility functions
-        File = fileUtil{}
-)
-
-type fileUtil struct{}
-
-// ReadByLines reads a file and calls the handler for each line.
-func (fu fileUtil) ReadByLines(filePath string, handler func(line string) error) error <span class="cov0" title="0">{
-        var f *os.File
-        var err error
-        if f, err = os.Open(filePath); err == nil </span><span class="cov0" title="0">{
-                defer f.Close()
-                var line string
-                scanner := bufio.NewScanner(f)
-                for scanner.Scan() </span><span class="cov0" title="0">{
-                        line = scanner.Text()
-                        err = handler(line)
-                        if err != nil </span><span class="cov0" title="0">{
-                                return err
-                        }</span>
-                }
-        }
-        <span class="cov0" title="0">return err</span>
-
-}
-
-// ReadByChunks reads a file in `chunkSize` pieces, dispatched to the handler.
-func (fu fileUtil) ReadByChunks(filePath string, chunkSize int, handler func(line []byte) error) error <span class="cov0" title="0">{
-        var f *os.File
-        var err error
-        if f, err = os.Open(filePath); err == nil </span><span class="cov0" title="0">{
-                defer f.Close()
-
-                chunk := make([]byte, chunkSize)
-                for </span><span class="cov0" title="0">{
-                        readBytes, err := f.Read(chunk)
-                        if err == io.EOF </span><span class="cov0" title="0">{
-                                break</span>
-                        }
-                        <span class="cov0" title="0">readData := chunk[:readBytes]
-                        err = handler(readData)
-                        if err != nil </span><span class="cov0" title="0">{
-                                return err
-                        }</span>
-                }
-        }
-        <span class="cov0" title="0">return err</span>
-}
-</pre>
-		
-		<pre class="file" id="file63" style="display: none">package util
-
-import (
-        "math"
-)
-
-const (
-        _pi   = math.Pi
-        _2pi  = 2 * math.Pi
-        _3pi4 = (3 * math.Pi) / 4.0
-        _4pi3 = (4 * math.Pi) / 3.0
-        _3pi2 = (3 * math.Pi) / 2.0
-        _5pi4 = (5 * math.Pi) / 4.0
-        _7pi4 = (7 * math.Pi) / 4.0
-        _pi2  = math.Pi / 2.0
-        _pi4  = math.Pi / 4.0
-        _d2r  = (math.Pi / 180.0)
-        _r2d  = (180.0 / math.Pi)
-)
-
-var (
-        // Math contains helper methods for common math operations.
-        Math = &amp;mathUtil{}
-)
-
-type mathUtil struct{}
-
-// Max returns the maximum value of a group of floats.
-func (m mathUtil) Max(values ...float64) float64 <span class="cov0" title="0">{
-        if len(values) == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-        <span class="cov0" title="0">max := values[0]
-        for _, v := range values </span><span class="cov0" title="0">{
-                if max &lt; v </span><span class="cov0" title="0">{
-                        max = v
-                }</span>
-        }
-        <span class="cov0" title="0">return max</span>
-}
-
-// MinAndMax returns both the min and max in one pass.
-func (m mathUtil) MinAndMax(values ...float64) (min float64, max float64) <span class="cov8" title="1">{
-        if len(values) == 0 </span><span class="cov8" title="1">{
-                return
-        }</span>
-        <span class="cov8" title="1">min = values[0]
-        max = values[0]
-        for _, v := range values[1:] </span><span class="cov8" title="1">{
-                if max &lt; v </span><span class="cov8" title="1">{
-                        max = v
-                }</span>
-                <span class="cov8" title="1">if min &gt; v </span><span class="cov8" title="1">{
-                        min = v
-                }</span>
-        }
-        <span class="cov8" title="1">return</span>
-}
-
-// GetRoundToForDelta returns a `roundTo` value for a given delta.
-func (m mathUtil) GetRoundToForDelta(delta float64) float64 <span class="cov8" title="1">{
-        startingDeltaBound := math.Pow(10.0, 10.0)
-        for cursor := startingDeltaBound; cursor &gt; 0; cursor /= 10.0 </span><span class="cov8" title="1">{
-                if delta &gt; cursor </span><span class="cov8" title="1">{
-                        return cursor / 10.0
-                }</span>
-        }
-
-        <span class="cov0" title="0">return 0.0</span>
-}
-
-// RoundUp rounds up to a given roundTo value.
-func (m mathUtil) RoundUp(value, roundTo float64) float64 <span class="cov8" title="1">{
-        if roundTo &lt; 0.000000000000001 </span><span class="cov8" title="1">{
-                return value
-        }</span>
-        <span class="cov8" title="1">d1 := math.Ceil(value / roundTo)
-        return d1 * roundTo</span>
-}
-
-// RoundDown rounds down to a given roundTo value.
-func (m mathUtil) RoundDown(value, roundTo float64) float64 <span class="cov8" title="1">{
-        if roundTo &lt; 0.000000000000001 </span><span class="cov8" title="1">{
-                return value
-        }</span>
-        <span class="cov8" title="1">d1 := math.Floor(value / roundTo)
-        return d1 * roundTo</span>
-}
-
-// Normalize returns a set of numbers on the interval [0,1] for a given set of inputs.
-// An example: 4,3,2,1 =&gt; 0.4, 0.3, 0.2, 0.1
-// Caveat; the total may be &lt; 1.0; there are going to be issues with irrational numbers etc.
-func (m mathUtil) Normalize(values ...float64) []float64 <span class="cov8" title="1">{
-        var total float64
-        for _, v := range values </span><span class="cov8" title="1">{
-                total += v
-        }</span>
-        <span class="cov8" title="1">output := make([]float64, len(values))
-        for x, v := range values </span><span class="cov8" title="1">{
-                output[x] = m.RoundDown(v/total, 0.0001)
-        }</span>
-        <span class="cov8" title="1">return output</span>
-}
-
-// MinInt returns the minimum of a set of integers.
-func (m mathUtil) MinInt(values ...int) int <span class="cov0" title="0">{
-        min := math.MaxInt32
-        for _, v := range values </span><span class="cov0" title="0">{
-                if v &lt; min </span><span class="cov0" title="0">{
-                        min = v
-                }</span>
-        }
-        <span class="cov0" title="0">return min</span>
-}
-
-// MaxInt returns the maximum of a set of integers.
-func (m mathUtil) MaxInt(values ...int) int <span class="cov0" title="0">{
-        max := math.MinInt32
-        for _, v := range values </span><span class="cov0" title="0">{
-                if v &gt; max </span><span class="cov0" title="0">{
-                        max = v
-                }</span>
-        }
-        <span class="cov0" title="0">return max</span>
-}
-
-// AbsInt returns the absolute value of an integer.
-func (m mathUtil) AbsInt(value int) int <span class="cov0" title="0">{
-        if value &lt; 0 </span><span class="cov0" title="0">{
-                return -value
-        }</span>
-        <span class="cov0" title="0">return value</span>
-}
-
-// AbsInt64 returns the absolute value of a long.
-func (m mathUtil) AbsInt64(value int64) int64 <span class="cov0" title="0">{
-        if value &lt; 0 </span><span class="cov0" title="0">{
-                return -value
-        }</span>
-        <span class="cov0" title="0">return value</span>
-}
-
-// Mean returns the mean of a set of values
-func (m mathUtil) Mean(values ...float64) float64 <span class="cov0" title="0">{
-        return m.Sum(values...) / float64(len(values))
-}</span>
-
-// MeanInt returns the mean of a set of integer values.
-func (m mathUtil) MeanInt(values ...int) int <span class="cov0" title="0">{
-        return m.SumInt(values...) / len(values)
-}</span>
-
-// Sum sums a set of values.
-func (m mathUtil) Sum(values ...float64) float64 <span class="cov0" title="0">{
-        var total float64
-        for _, v := range values </span><span class="cov0" title="0">{
-                total += v
-        }</span>
-        <span class="cov0" title="0">return total</span>
-}
-
-// SumInt sums a set of values.
-func (m mathUtil) SumInt(values ...int) int <span class="cov0" title="0">{
-        var total int
-        for _, v := range values </span><span class="cov0" title="0">{
-                total += v
-        }</span>
-        <span class="cov0" title="0">return total</span>
-}
-
-// PercentDifference computes the percentage difference between two values.
-// The formula is (v2-v1)/v1.
-func (m mathUtil) PercentDifference(v1, v2 float64) float64 <span class="cov8" title="1">{
-        if v1 == 0 </span><span class="cov0" title="0">{
-                return 0
-        }</span>
-        <span class="cov8" title="1">return (v2 - v1) / v1</span>
-}
-
-// DegreesToRadians returns degrees as radians.
-func (m mathUtil) DegreesToRadians(degrees float64) float64 <span class="cov8" title="1">{
-        return degrees * _d2r
-}</span>
-
-// RadiansToDegrees translates a radian value to a degree value.
-func (m mathUtil) RadiansToDegrees(value float64) float64 <span class="cov8" title="1">{
-        return math.Mod(value, _2pi) * _r2d
-}</span>
-
-// PercentToRadians converts a normalized value (0,1) to radians.
-func (m mathUtil) PercentToRadians(pct float64) float64 <span class="cov8" title="1">{
-        return m.DegreesToRadians(360.0 * pct)
-}</span>
-
-// RadianAdd adds a delta to a base in radians.
-func (m mathUtil) RadianAdd(base, delta float64) float64 <span class="cov8" title="1">{
-        value := base + delta
-        if value &gt; _2pi </span><span class="cov8" title="1">{
-                return math.Mod(value, _2pi)
-        }</span> else<span class="cov8" title="1"> if value &lt; 0 </span><span class="cov8" title="1">{
-                return math.Mod(_2pi+value, _2pi)
-        }</span>
-        <span class="cov8" title="1">return value</span>
-}
-
-// DegreesAdd adds a delta to a base in radians.
-func (m mathUtil) DegreesAdd(baseDegrees, deltaDegrees float64) float64 <span class="cov0" title="0">{
-        value := baseDegrees + deltaDegrees
-        if value &gt; _2pi </span><span class="cov0" title="0">{
-                return math.Mod(value, 360.0)
-        }</span> else<span class="cov0" title="0"> if value &lt; 0 </span><span class="cov0" title="0">{
-                return math.Mod(360.0+value, 360.0)
-        }</span>
-        <span class="cov0" title="0">return value</span>
-}
-
-// DegreesToCompass returns the degree value in compass / clock orientation.
-func (m mathUtil) DegreesToCompass(deg float64) float64 <span class="cov0" title="0">{
-        return m.DegreesAdd(deg, -90.0)
-}</span>
-
-// CirclePoint returns the absolute position of a circle diameter point given
-// by the radius and the theta.
-func (m mathUtil) CirclePoint(cx, cy int, radius, thetaRadians float64) (x, y int) <span class="cov0" title="0">{
-        x = cx + int(radius*math.Sin(thetaRadians))
-        y = cy - int(radius*math.Cos(thetaRadians))
-        return
-}</span>
-
-func (m mathUtil) RotateCoordinate(cx, cy, x, y int, thetaRadians float64) (rx, ry int) <span class="cov8" title="1">{
-        tempX, tempY := float64(x-cx), float64(y-cy)
-        rotatedX := tempX*math.Cos(thetaRadians) - tempY*math.Sin(thetaRadians)
-        rotatedY := tempX*math.Sin(thetaRadians) + tempY*math.Cos(thetaRadians)
-        rx = int(rotatedX) + cx
-        ry = int(rotatedY) + cy
-        return
-}</span>
-</pre>
-		
-		<pre class="file" id="file64" style="display: none">package util
-
-import "time"
-
-var (
-        // Time contains time utility functions.
-        Time = timeUtil{}
-)
-
-type timeUtil struct{}
-
-// Millis returns the duration as milliseconds.
-func (tu timeUtil) Millis(d time.Duration) float64 <span class="cov0" title="0">{
-        return float64(d) / float64(time.Millisecond)
-}</span>
-
-// TimeToFloat64 returns a float64 representation of a time.
-func (tu timeUtil) ToFloat64(t time.Time) float64 <span class="cov0" title="0">{
-        return float64(t.UnixNano())
-}</span>
-
-// Float64ToTime returns a time from a float64.
-func (tu timeUtil) FromFloat64(tf float64) time.Time <span class="cov0" title="0">{
-        return time.Unix(0, int64(tf))
-}</span>
-
-func (tu timeUtil) DiffDays(t1, t2 time.Time) (days int) <span class="cov8" title="1">{
-        t1n := t1.Unix()
-        t2n := t2.Unix()
-        var diff int64
-        if t1n &gt; t2n </span><span class="cov0" title="0">{
-                diff = t1n - t2n //yields seconds
-        }</span> else<span class="cov8" title="1"> {
-                diff = t2n - t1n //yields seconds
-        }</span>
-        <span class="cov8" title="1">return int(diff / (_secondsPerDay))</span>
-}
-
-func (tu timeUtil) DiffHours(t1, t2 time.Time) (hours int) <span class="cov8" title="1">{
-        t1n := t1.Unix()
-        t2n := t2.Unix()
-        var diff int64
-        if t1n &gt; t2n </span><span class="cov0" title="0">{
-                diff = t1n - t2n
-        }</span> else<span class="cov8" title="1"> {
-                diff = t2n - t1n
-        }</span>
-        <span class="cov8" title="1">return int(diff / (_secondsPerHour))</span>
-}
-
-// Start returns the earliest (min) time in a list of times.
-func (tu timeUtil) Start(times ...time.Time) time.Time <span class="cov0" title="0">{
-        if len(times) == 0 </span><span class="cov0" title="0">{
-                return time.Time{}
-        }</span>
-
-        <span class="cov0" title="0">start := times[0]
-        for _, t := range times[1:] </span><span class="cov0" title="0">{
-                if t.Before(start) </span><span class="cov0" title="0">{
-                        start = t
-                }</span>
-        }
-        <span class="cov0" title="0">return start</span>
-}
-
-// Start returns the earliest (min) time in a list of times.
-func (tu timeUtil) End(times ...time.Time) time.Time <span class="cov0" title="0">{
-        if len(times) == 0 </span><span class="cov0" title="0">{
-                return time.Time{}
-        }</span>
-
-        <span class="cov0" title="0">end := times[0]
-        for _, t := range times[1:] </span><span class="cov0" title="0">{
-                if t.After(end) </span><span class="cov0" title="0">{
-                        end = t
-                }</span>
-        }
-        <span class="cov0" title="0">return end</span>
-}
-
-// StartAndEnd returns the start and end of a given set of time in one pass.
-func (tu timeUtil) StartAndEnd(values ...time.Time) (start time.Time, end time.Time) <span class="cov8" title="1">{
-        if len(values) == 0 </span><span class="cov8" title="1">{
-                return
-        }</span>
-
-        <span class="cov8" title="1">start = values[0]
-        end = values[0]
-
-        for _, v := range values[1:] </span><span class="cov8" title="1">{
-                if end.Before(v) </span><span class="cov8" title="1">{
-                        end = v
-                }</span>
-                <span class="cov8" title="1">if start.After(v) </span><span class="cov8" title="1">{
-                        start = v
-                }</span>
-        }
-        <span class="cov8" title="1">return</span>
-}
-</pre>
-		
-		<pre class="file" id="file65" style="display: none">package chart
-
-import util "github.com/wcharczuk/go-chart/util"
-
-// Value is a chart value.
-type Value struct {
-        Style Style
-        Label string
-        Value float64
-}
-
-// Values is an array of Value.
-type Values []Value
-
-// Values returns the values.
-func (vs Values) Values() []float64 <span class="cov8" title="1">{
-        values := make([]float64, len(vs))
-        for index, v := range vs </span><span class="cov8" title="1">{
-                values[index] = v.Value
-        }</span>
-        <span class="cov8" title="1">return values</span>
-}
-
-// ValuesNormalized returns normalized values.
-func (vs Values) ValuesNormalized() []float64 <span class="cov8" title="1">{
-        return util.Math.Normalize(vs.Values()...)
-}</span>
-
-// Normalize returns the values normalized.
-func (vs Values) Normalize() []Value <span class="cov8" title="1">{
-        var output []Value
-        var total float64
-
-        for _, v := range vs </span><span class="cov8" title="1">{
-                total += v.Value
-        }</span>
-
-        <span class="cov8" title="1">for _, v := range vs </span><span class="cov8" title="1">{
-                if v.Value &gt; 0 </span><span class="cov8" title="1">{
-                        output = append(output, Value{
-                                Style: v.Style,
-                                Label: v.Label,
-                                Value: util.Math.RoundDown(v.Value/total, 0.0001),
-                        })
-                }</span>
-        }
-        <span class="cov8" title="1">return output</span>
-}
-
-// Value2 is a two axis value.
-type Value2 struct {
-        Style          Style
-        Label          string
-        XValue, YValue float64
-}
-</pre>
-		
-		<pre class="file" id="file66" style="display: none">package chart
-
-import (
-        "fmt"
-        "strconv"
-        "time"
-)
-
-// ValueFormatter is a function that takes a value and produces a string.
-type ValueFormatter func(v interface{}) string
-
-// TimeValueFormatter is a ValueFormatter for timestamps.
-func TimeValueFormatter(v interface{}) string <span class="cov8" title="1">{
-        return formatTime(v, DefaultDateFormat)
-}</span>
-
-// TimeHourValueFormatter is a ValueFormatter for timestamps.
-func TimeHourValueFormatter(v interface{}) string <span class="cov0" title="0">{
-        return formatTime(v, DefaultDateHourFormat)
-}</span>
-
-// TimeMinuteValueFormatter is a ValueFormatter for timestamps.
-func TimeMinuteValueFormatter(v interface{}) string <span class="cov0" title="0">{
-        return formatTime(v, DefaultDateMinuteFormat)
-}</span>
-
-// TimeDateValueFormatter is a ValueFormatter for timestamps.
-func TimeDateValueFormatter(v interface{}) string <span class="cov0" title="0">{
-        return formatTime(v, "2006-01-02")
-}</span>
-
-// TimeValueFormatterWithFormat returns a time formatter with a given format.
-func TimeValueFormatterWithFormat(format string) ValueFormatter <span class="cov0" title="0">{
-        return func(v interface{}) string </span><span class="cov0" title="0">{
-                return formatTime(v, format)
-        }</span>
-}
-
-// TimeValueFormatterWithFormat is a ValueFormatter for timestamps with a given format.
-func formatTime(v interface{}, dateFormat string) string <span class="cov8" title="1">{
-        if typed, isTyped := v.(time.Time); isTyped </span><span class="cov8" title="1">{
-                return typed.Format(dateFormat)
-        }</span>
-        <span class="cov8" title="1">if typed, isTyped := v.(int64); isTyped </span><span class="cov0" title="0">{
-                return time.Unix(0, typed).Format(dateFormat)
-        }</span>
-        <span class="cov8" title="1">if typed, isTyped := v.(float64); isTyped </span><span class="cov8" title="1">{
-                return time.Unix(0, int64(typed)).Format(dateFormat)
-        }</span>
-        <span class="cov0" title="0">return ""</span>
-}
-
-// IntValueFormatter is a ValueFormatter for float64.
-func IntValueFormatter(v interface{}) string <span class="cov0" title="0">{
-        switch v.(type) </span>{
-        case int:<span class="cov0" title="0">
-                return strconv.Itoa(v.(int))</span>
-        case int64:<span class="cov0" title="0">
-                return strconv.FormatInt(v.(int64), 10)</span>
-        case float32:<span class="cov0" title="0">
-                return strconv.FormatInt(int64(v.(float32)), 10)</span>
-        case float64:<span class="cov0" title="0">
-                return strconv.FormatInt(int64(v.(float64)), 10)</span>
-        default:<span class="cov0" title="0">
-                return ""</span>
-        }
-}
-
-// FloatValueFormatter is a ValueFormatter for float64.
-func FloatValueFormatter(v interface{}) string <span class="cov8" title="1">{
-        return FloatValueFormatterWithFormat(v, DefaultFloatFormat)
-}</span>
-
-// PercentValueFormatter is a formatter for percent values.
-// NOTE: it normalizes the values, i.e. multiplies by 100.0.
-func PercentValueFormatter(v interface{}) string <span class="cov0" title="0">{
-        if typed, isTyped := v.(float64); isTyped </span><span class="cov0" title="0">{
-                return FloatValueFormatterWithFormat(typed*100.0, DefaultPercentValueFormat)
-        }</span>
-        <span class="cov0" title="0">return ""</span>
-}
-
-// FloatValueFormatterWithFormat is a ValueFormatter for float64 with a given format.
-func FloatValueFormatterWithFormat(v interface{}, floatFormat string) string <span class="cov8" title="1">{
-        if typed, isTyped := v.(int); isTyped </span><span class="cov8" title="1">{
-                return fmt.Sprintf(floatFormat, float64(typed))
-        }</span>
-        <span class="cov8" title="1">if typed, isTyped := v.(int64); isTyped </span><span class="cov8" title="1">{
-                return fmt.Sprintf(floatFormat, float64(typed))
-        }</span>
-        <span class="cov8" title="1">if typed, isTyped := v.(float32); isTyped </span><span class="cov8" title="1">{
-                return fmt.Sprintf(floatFormat, typed)
-        }</span>
-        <span class="cov8" title="1">if typed, isTyped := v.(float64); isTyped </span><span class="cov8" title="1">{
-                return fmt.Sprintf(floatFormat, typed)
-        }</span>
-        <span class="cov0" title="0">return ""</span>
-}
-</pre>
-		
-		<pre class="file" id="file67" style="display: none">package chart
-
-import (
-        "bytes"
-        "fmt"
-        "io"
-        "math"
-        "strings"
-
-        "golang.org/x/image/font"
-
-        "github.com/golang/freetype/truetype"
-        "github.com/wcharczuk/go-chart/drawing"
-        "github.com/wcharczuk/go-chart/util"
-)
-
-// SVG returns a new png/raster renderer.
-func SVG(width, height int) (Renderer, error) <span class="cov8" title="1">{
-        buffer := bytes.NewBuffer([]byte{})
-        canvas := newCanvas(buffer)
-        canvas.Start(width, height)
-        return &amp;vectorRenderer{
-                b:   buffer,
-                c:   canvas,
-                s:   &amp;Style{},
-                p:   []string{},
-                dpi: DefaultDPI,
-        }, nil
-}</span>
-
-// vectorRenderer renders chart commands to a bitmap.
-type vectorRenderer struct {
-        dpi float64
-        b   *bytes.Buffer
-        c   *canvas
-        s   *Style
-        p   []string
-        fc  *font.Drawer
-}
-
-func (vr *vectorRenderer) ResetStyle() <span class="cov0" title="0">{
-        vr.s = &amp;Style{Font: vr.s.Font}
-        vr.fc = nil
-}</span>
-
-// GetDPI returns the dpi.
-func (vr *vectorRenderer) GetDPI() float64 <span class="cov0" title="0">{
-        return vr.dpi
-}</span>
-
-// SetDPI implements the interface method.
-func (vr *vectorRenderer) SetDPI(dpi float64) <span class="cov8" title="1">{
-        vr.dpi = dpi
-        vr.c.dpi = dpi
-}</span>
-
-// SetClassName implements the interface method.
-func (vr *vectorRenderer) SetClassName(classname string) <span class="cov0" title="0">{
-        vr.s.ClassName = classname
-}</span>
-
-// SetStrokeColor implements the interface method.
-func (vr *vectorRenderer) SetStrokeColor(c drawing.Color) <span class="cov0" title="0">{
-        vr.s.StrokeColor = c
-}</span>
-
-// SetFillColor implements the interface method.
-func (vr *vectorRenderer) SetFillColor(c drawing.Color) <span class="cov0" title="0">{
-        vr.s.FillColor = c
-}</span>
-
-// SetLineWidth implements the interface method.
-func (vr *vectorRenderer) SetStrokeWidth(width float64) <span class="cov0" title="0">{
-        vr.s.StrokeWidth = width
-}</span>
-
-// StrokeDashArray sets the stroke dash array.
-func (vr *vectorRenderer) SetStrokeDashArray(dashArray []float64) <span class="cov0" title="0">{
-        vr.s.StrokeDashArray = dashArray
-}</span>
-
-// MoveTo implements the interface method.
-func (vr *vectorRenderer) MoveTo(x, y int) <span class="cov8" title="1">{
-        vr.p = append(vr.p, fmt.Sprintf("M %d %d", x, y))
-}</span>
-
-// LineTo implements the interface method.
-func (vr *vectorRenderer) LineTo(x, y int) <span class="cov8" title="1">{
-        vr.p = append(vr.p, fmt.Sprintf("L %d %d", x, y))
-}</span>
-
-// QuadCurveTo draws a quad curve.
-func (vr *vectorRenderer) QuadCurveTo(cx, cy, x, y int) <span class="cov0" title="0">{
-        vr.p = append(vr.p, fmt.Sprintf("Q%d,%d %d,%d", cx, cy, x, y))
-}</span>
-
-func (vr *vectorRenderer) ArcTo(cx, cy int, rx, ry, startAngle, delta float64) <span class="cov0" title="0">{
-        startAngle = util.Math.RadianAdd(startAngle, _pi2)
-        endAngle := util.Math.RadianAdd(startAngle, delta)
-
-        startx := cx + int(rx*math.Sin(startAngle))
-        starty := cy - int(ry*math.Cos(startAngle))
-
-        if len(vr.p) &gt; 0 </span><span class="cov0" title="0">{
-                vr.p = append(vr.p, fmt.Sprintf("L %d %d", startx, starty))
-        }</span> else<span class="cov0" title="0"> {
-                vr.p = append(vr.p, fmt.Sprintf("M %d %d", startx, starty))
-        }</span>
-
-        <span class="cov0" title="0">endx := cx + int(rx*math.Sin(endAngle))
-        endy := cy - int(ry*math.Cos(endAngle))
-
-        dd := util.Math.RadiansToDegrees(delta)
-
-        largeArcFlag := 0
-        if delta &gt; _pi </span><span class="cov0" title="0">{
-                largeArcFlag = 1
-        }</span>
-
-        <span class="cov0" title="0">vr.p = append(vr.p, fmt.Sprintf("A %d %d %0.2f %d 1 %d %d", int(rx), int(ry), dd, largeArcFlag, endx, endy))</span>
-}
-
-// Close closes a shape.
-func (vr *vectorRenderer) Close() <span class="cov8" title="1">{
-        vr.p = append(vr.p, fmt.Sprintf("Z"))
-}</span>
-
-// Stroke draws the path with no fill.
-func (vr *vectorRenderer) Stroke() <span class="cov0" title="0">{
-        vr.drawPath(vr.s.GetStrokeOptions())
-}</span>
-
-// Fill draws the path with no stroke.
-func (vr *vectorRenderer) Fill() <span class="cov0" title="0">{
-        vr.drawPath(vr.s.GetFillOptions())
-}</span>
-
-// FillStroke draws the path with both fill and stroke.
-func (vr *vectorRenderer) FillStroke() <span class="cov8" title="1">{
-        vr.drawPath(vr.s.GetFillAndStrokeOptions())
-}</span>
-
-// drawPath draws a path.
-func (vr *vectorRenderer) drawPath(s Style) <span class="cov8" title="1">{
-        vr.c.Path(strings.Join(vr.p, "\n"), vr.s.GetFillAndStrokeOptions())
-        vr.p = []string{} // clear the path
-}</span>
-
-// Circle implements the interface method.
-func (vr *vectorRenderer) Circle(radius float64, x, y int) <span class="cov0" title="0">{
-        vr.c.Circle(x, y, int(radius), vr.s.GetFillAndStrokeOptions())
-}</span>
-
-// SetFont implements the interface method.
-func (vr *vectorRenderer) SetFont(f *truetype.Font) <span class="cov8" title="1">{
-        vr.s.Font = f
-}</span>
-
-// SetFontColor implements the interface method.
-func (vr *vectorRenderer) SetFontColor(c drawing.Color) <span class="cov0" title="0">{
-        vr.s.FontColor = c
-}</span>
-
-// SetFontSize implements the interface method.
-func (vr *vectorRenderer) SetFontSize(size float64) <span class="cov8" title="1">{
-        vr.s.FontSize = size
-}</span>
-
-// Text draws a text blob.
-func (vr *vectorRenderer) Text(body string, x, y int) <span class="cov0" title="0">{
-        vr.c.Text(x, y, body, vr.s.GetTextOptions())
-}</span>
-
-// MeasureText uses the truetype font drawer to measure the width of text.
-func (vr *vectorRenderer) MeasureText(body string) (box Box) <span class="cov8" title="1">{
-        if vr.s.GetFont() != nil </span><span class="cov8" title="1">{
-                vr.fc = &amp;font.Drawer{
-                        Face: truetype.NewFace(vr.s.GetFont(), &amp;truetype.Options{
-                                DPI:  vr.dpi,
-                                Size: vr.s.FontSize,
-                        }),
-                }
-                w := vr.fc.MeasureString(body).Ceil()
-
-                box.Right = w
-                box.Bottom = int(drawing.PointsToPixels(vr.dpi, vr.s.FontSize))
-                if vr.c.textTheta == nil </span><span class="cov8" title="1">{
-                        return
-                }</span>
-                <span class="cov0" title="0">box = box.Corners().Rotate(util.Math.RadiansToDegrees(*vr.c.textTheta)).Box()</span>
-        }
-        <span class="cov0" title="0">return</span>
-}
-
-// SetTextRotation sets the text rotation.
-func (vr *vectorRenderer) SetTextRotation(radians float64) <span class="cov0" title="0">{
-        vr.c.textTheta = &amp;radians
-}</span>
-
-// ClearTextRotation clears the text rotation.
-func (vr *vectorRenderer) ClearTextRotation() <span class="cov0" title="0">{
-        vr.c.textTheta = nil
-}</span>
-
-// Save saves the renderer's contents to a writer.
-func (vr *vectorRenderer) Save(w io.Writer) error <span class="cov8" title="1">{
-        vr.c.End()
-        _, err := w.Write(vr.b.Bytes())
-        return err
-}</span>
-
-func newCanvas(w io.Writer) *canvas <span class="cov8" title="1">{
-        return &amp;canvas{
-                w:   w,
-                dpi: DefaultDPI,
-        }
-}</span>
-
-type canvas struct {
-        w         io.Writer
-        dpi       float64
-        textTheta *float64
-        width     int
-        height    int
-}
-
-func (c *canvas) Start(width, height int) <span class="cov8" title="1">{
-        c.width = width
-        c.height = height
-        c.w.Write([]byte(fmt.Sprintf(`&lt;svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="%d" height="%d"&gt;\n`, c.width, c.height)))
-}</span>
-
-func (c *canvas) Path(d string, style Style) <span class="cov8" title="1">{
-        var strokeDashArrayProperty string
-        if len(style.StrokeDashArray) &gt; 0 </span><span class="cov0" title="0">{
-                strokeDashArrayProperty = c.getStrokeDashArray(style)
-        }</span>
-        <span class="cov8" title="1">c.w.Write([]byte(fmt.Sprintf(`&lt;path %s d="%s" %s/&gt;`, strokeDashArrayProperty, d, c.styleAsSVG(style))))</span>
-}
-
-func (c *canvas) Text(x, y int, body string, style Style) <span class="cov0" title="0">{
-        if c.textTheta == nil </span><span class="cov0" title="0">{
-                c.w.Write([]byte(fmt.Sprintf(`&lt;text x="%d" y="%d" %s&gt;%s&lt;/text&gt;`, x, y, c.styleAsSVG(style), body)))
-        }</span> else<span class="cov0" title="0"> {
-                transform := fmt.Sprintf(` transform="rotate(%0.2f,%d,%d)"`, util.Math.RadiansToDegrees(*c.textTheta), x, y)
-                c.w.Write([]byte(fmt.Sprintf(`&lt;text x="%d" y="%d" %s%s&gt;%s&lt;/text&gt;`, x, y, c.styleAsSVG(style), transform, body)))
-        }</span>
-}
-
-func (c *canvas) Circle(x, y, r int, style Style) <span class="cov0" title="0">{
-        c.w.Write([]byte(fmt.Sprintf(`&lt;circle cx="%d" cy="%d" r="%d" %s/&gt;`, x, y, r, c.styleAsSVG(style))))
-}</span>
-
-func (c *canvas) End() <span class="cov8" title="1">{
-        c.w.Write([]byte("&lt;/svg&gt;"))
-}</span>
-
-// getStrokeDashArray returns the stroke-dasharray property of a style.
-func (c *canvas) getStrokeDashArray(s Style) string <span class="cov0" title="0">{
-        if len(s.StrokeDashArray) &gt; 0 </span><span class="cov0" title="0">{
-                var values []string
-                for _, v := range s.StrokeDashArray </span><span class="cov0" title="0">{
-                        values = append(values, fmt.Sprintf("%0.1f", v))
-                }</span>
-                <span class="cov0" title="0">return "stroke-dasharray=\"" + strings.Join(values, ", ") + "\""</span>
-        }
-        <span class="cov0" title="0">return ""</span>
-}
-
-// GetFontFace returns the font face for the style.
-func (c *canvas) getFontFace(s Style) string <span class="cov8" title="1">{
-        family := "sans-serif"
-        if s.GetFont() != nil </span><span class="cov8" title="1">{
-                name := s.GetFont().Name(truetype.NameIDFontFamily)
-                if len(name) != 0 </span><span class="cov8" title="1">{
-                        family = fmt.Sprintf(`'%s',%s`, name, family)
-                }</span>
-        }
-        <span class="cov8" title="1">return fmt.Sprintf("font-family:%s", family)</span>
-}
-
-// styleAsSVG returns the style as a svg style or class string.
-func (c *canvas) styleAsSVG(s Style) string <span class="cov8" title="1">{
-        if s.ClassName != "" </span><span class="cov8" title="1">{
-                return fmt.Sprintf("class=\"%s\"", s.ClassName)
-        }</span>
-        <span class="cov8" title="1">sw := s.StrokeWidth
-        sc := s.StrokeColor
-        fc := s.FillColor
-        fs := s.FontSize
-        fnc := s.FontColor
-
-        var pieces []string
-
-        if sw != 0 </span><span class="cov8" title="1">{
-                pieces = append(pieces, "stroke-width:"+fmt.Sprintf("%d", int(sw)))
-        }</span> else<span class="cov8" title="1"> {
-                pieces = append(pieces, "stroke-width:0")
-        }</span>
-
-        <span class="cov8" title="1">if !sc.IsZero() </span><span class="cov8" title="1">{
-                pieces = append(pieces, "stroke:"+sc.String())
-        }</span> else<span class="cov8" title="1"> {
-                pieces = append(pieces, "stroke:none")
-        }</span>
-
-        <span class="cov8" title="1">if !fnc.IsZero() </span><span class="cov8" title="1">{
-                pieces = append(pieces, "fill:"+fnc.String())
-        }</span> else<span class="cov8" title="1"> if !fc.IsZero() </span><span class="cov0" title="0">{
-                pieces = append(pieces, "fill:"+fc.String())
-        }</span> else<span class="cov8" title="1"> {
-                pieces = append(pieces, "fill:none")
-        }</span>
-
-        <span class="cov8" title="1">if fs != 0 </span><span class="cov0" title="0">{
-                pieces = append(pieces, "font-size:"+fmt.Sprintf("%.1fpx", drawing.PointsToPixels(c.dpi, fs)))
-        }</span>
-
-        <span class="cov8" title="1">if s.Font != nil </span><span class="cov8" title="1">{
-                pieces = append(pieces, c.getFontFace(s))
-        }</span>
-        <span class="cov8" title="1">return fmt.Sprintf("style=\"%s\"", strings.Join(pieces, ";"))</span>
-}
-</pre>
-		
-		<pre class="file" id="file68" style="display: none">package chart
-
-import "github.com/wcharczuk/go-chart/drawing"
-
-var viridisColors = [256]drawing.Color{
-        drawing.Color{R: 0x44, G: 0x1, B: 0x54, A: 0xff},
-        drawing.Color{R: 0x44, G: 0x2, B: 0x55, A: 0xff},
-        drawing.Color{R: 0x45, G: 0x3, B: 0x57, A: 0xff},
-        drawing.Color{R: 0x45, G: 0x5, B: 0x58, A: 0xff},
-        drawing.Color{R: 0x45, G: 0x6, B: 0x5a, A: 0xff},
-        drawing.Color{R: 0x46, G: 0x8, B: 0x5b, A: 0xff},
-        drawing.Color{R: 0x46, G: 0x9, B: 0x5d, A: 0xff},
-        drawing.Color{R: 0x46, G: 0xb, B: 0x5e, A: 0xff},
-        drawing.Color{R: 0x46, G: 0xc, B: 0x60, A: 0xff},
-        drawing.Color{R: 0x47, G: 0xe, B: 0x61, A: 0xff},
-        drawing.Color{R: 0x47, G: 0xf, B: 0x62, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x11, B: 0x64, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x12, B: 0x65, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x14, B: 0x66, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x15, B: 0x68, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x16, B: 0x69, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x18, B: 0x6a, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x19, B: 0x6c, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x1a, B: 0x6d, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x1c, B: 0x6e, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x1d, B: 0x6f, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x1e, B: 0x70, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x20, B: 0x71, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x21, B: 0x73, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x22, B: 0x74, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x24, B: 0x75, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x25, B: 0x76, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x26, B: 0x77, A: 0xff},
-        drawing.Color{R: 0x48, G: 0x27, B: 0x78, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x29, B: 0x79, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x2a, B: 0x79, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x2b, B: 0x7a, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x2c, B: 0x7b, A: 0xff},
-        drawing.Color{R: 0x47, G: 0x2e, B: 0x7c, A: 0xff},
-        drawing.Color{R: 0x46, G: 0x2f, B: 0x7d, A: 0xff},
-        drawing.Color{R: 0x46, G: 0x30, B: 0x7e, A: 0xff},
-        drawing.Color{R: 0x46, G: 0x31, B: 0x7e, A: 0xff},
-        drawing.Color{R: 0x46, G: 0x33, B: 0x7f, A: 0xff},
-        drawing.Color{R: 0x45, G: 0x34, B: 0x80, A: 0xff},
-        drawing.Color{R: 0x45, G: 0x35, B: 0x81, A: 0xff},
-        drawing.Color{R: 0x45, G: 0x36, B: 0x81, A: 0xff},
-        drawing.Color{R: 0x44, G: 0x38, B: 0x82, A: 0xff},
-        drawing.Color{R: 0x44, G: 0x39, B: 0x83, A: 0xff},
-        drawing.Color{R: 0x44, G: 0x3a, B: 0x83, A: 0xff},
-        drawing.Color{R: 0x43, G: 0x3b, B: 0x84, A: 0xff},
-        drawing.Color{R: 0x43, G: 0x3c, B: 0x84, A: 0xff},
-        drawing.Color{R: 0x43, G: 0x3e, B: 0x85, A: 0xff},
-        drawing.Color{R: 0x42, G: 0x3f, B: 0x85, A: 0xff},
-        drawing.Color{R: 0x42, G: 0x40, B: 0x86, A: 0xff},
-        drawing.Color{R: 0x41, G: 0x41, B: 0x86, A: 0xff},
-        drawing.Color{R: 0x41, G: 0x42, B: 0x87, A: 0xff},
-        drawing.Color{R: 0x41, G: 0x43, B: 0x87, A: 0xff},
-        drawing.Color{R: 0x40, G: 0x45, B: 0x88, A: 0xff},
-        drawing.Color{R: 0x40, G: 0x46, B: 0x88, A: 0xff},
-        drawing.Color{R: 0x3f, G: 0x47, B: 0x88, A: 0xff},
-        drawing.Color{R: 0x3f, G: 0x48, B: 0x89, A: 0xff},
-        drawing.Color{R: 0x3e, G: 0x49, B: 0x89, A: 0xff},
-        drawing.Color{R: 0x3e, G: 0x4a, B: 0x89, A: 0xff},
-        drawing.Color{R: 0x3d, G: 0x4b, B: 0x8a, A: 0xff},
-        drawing.Color{R: 0x3d, G: 0x4d, B: 0x8a, A: 0xff},
-        drawing.Color{R: 0x3c, G: 0x4e, B: 0x8a, A: 0xff},
-        drawing.Color{R: 0x3c, G: 0x4f, B: 0x8a, A: 0xff},
-        drawing.Color{R: 0x3b, G: 0x50, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x3b, G: 0x51, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x3a, G: 0x52, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x3a, G: 0x53, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x39, G: 0x54, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x39, G: 0x55, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x38, G: 0x56, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x38, G: 0x57, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x37, G: 0x58, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x37, G: 0x59, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x36, G: 0x5b, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x36, G: 0x5c, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x35, G: 0x5d, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x35, G: 0x5e, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x34, G: 0x5f, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x34, G: 0x60, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x33, G: 0x61, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x33, G: 0x62, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x33, G: 0x63, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x32, G: 0x64, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x32, G: 0x65, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x31, G: 0x66, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x31, G: 0x67, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x30, G: 0x68, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x30, G: 0x69, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2f, G: 0x6a, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2f, G: 0x6b, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2f, G: 0x6c, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2e, G: 0x6d, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2e, G: 0x6e, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2d, G: 0x6f, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2d, G: 0x70, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2d, G: 0x70, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2c, G: 0x71, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2c, G: 0x72, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2b, G: 0x73, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2b, G: 0x74, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2b, G: 0x75, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2a, G: 0x76, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x2a, G: 0x77, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x29, G: 0x78, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x29, G: 0x79, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x29, G: 0x7a, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x28, G: 0x7b, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x28, G: 0x7c, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x28, G: 0x7d, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x27, G: 0x7e, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x27, G: 0x7f, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x26, G: 0x80, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x26, G: 0x81, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x26, G: 0x82, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x25, G: 0x83, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x25, G: 0x83, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x25, G: 0x84, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x24, G: 0x85, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x24, G: 0x86, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x23, G: 0x87, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x23, G: 0x88, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x23, G: 0x89, B: 0x8e, A: 0xff},
-        drawing.Color{R: 0x22, G: 0x8a, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x22, G: 0x8b, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x22, G: 0x8c, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x21, G: 0x8d, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x21, G: 0x8e, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x21, G: 0x8f, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x20, G: 0x90, B: 0x8d, A: 0xff},
-        drawing.Color{R: 0x20, G: 0x91, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x20, G: 0x92, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x20, G: 0x93, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0x93, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0x94, B: 0x8c, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0x95, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0x96, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0x97, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x98, B: 0x8b, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x99, B: 0x8a, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x9a, B: 0x8a, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x9b, B: 0x8a, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x9c, B: 0x89, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x9d, B: 0x89, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x9e, B: 0x89, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0x9f, B: 0x88, A: 0xff},
-        drawing.Color{R: 0x1e, G: 0xa0, B: 0x88, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0xa1, B: 0x88, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0xa2, B: 0x87, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0xa3, B: 0x87, A: 0xff},
-        drawing.Color{R: 0x1f, G: 0xa3, B: 0x86, A: 0xff},
-        drawing.Color{R: 0x20, G: 0xa4, B: 0x86, A: 0xff},
-        drawing.Color{R: 0x20, G: 0xa5, B: 0x86, A: 0xff},
-        drawing.Color{R: 0x21, G: 0xa6, B: 0x85, A: 0xff},
-        drawing.Color{R: 0x21, G: 0xa7, B: 0x85, A: 0xff},
-        drawing.Color{R: 0x22, G: 0xa8, B: 0x84, A: 0xff},
-        drawing.Color{R: 0x23, G: 0xa9, B: 0x83, A: 0xff},
-        drawing.Color{R: 0x23, G: 0xaa, B: 0x83, A: 0xff},
-        drawing.Color{R: 0x24, G: 0xab, B: 0x82, A: 0xff},
-        drawing.Color{R: 0x25, G: 0xac, B: 0x82, A: 0xff},
-        drawing.Color{R: 0x26, G: 0xad, B: 0x81, A: 0xff},
-        drawing.Color{R: 0x27, G: 0xae, B: 0x81, A: 0xff},
-        drawing.Color{R: 0x28, G: 0xaf, B: 0x80, A: 0xff},
-        drawing.Color{R: 0x29, G: 0xaf, B: 0x7f, A: 0xff},
-        drawing.Color{R: 0x2a, G: 0xb0, B: 0x7f, A: 0xff},
-        drawing.Color{R: 0x2b, G: 0xb1, B: 0x7e, A: 0xff},
-        drawing.Color{R: 0x2c, G: 0xb2, B: 0x7d, A: 0xff},
-        drawing.Color{R: 0x2e, G: 0xb3, B: 0x7c, A: 0xff},
-        drawing.Color{R: 0x2f, G: 0xb4, B: 0x7c, A: 0xff},
-        drawing.Color{R: 0x30, G: 0xb5, B: 0x7b, A: 0xff},
-        drawing.Color{R: 0x32, G: 0xb6, B: 0x7a, A: 0xff},
-        drawing.Color{R: 0x33, G: 0xb7, B: 0x79, A: 0xff},
-        drawing.Color{R: 0x35, G: 0xb7, B: 0x79, A: 0xff},
-        drawing.Color{R: 0x36, G: 0xb8, B: 0x78, A: 0xff},
-        drawing.Color{R: 0x38, G: 0xb9, B: 0x77, A: 0xff},
-        drawing.Color{R: 0x39, G: 0xba, B: 0x76, A: 0xff},
-        drawing.Color{R: 0x3b, G: 0xbb, B: 0x75, A: 0xff},
-        drawing.Color{R: 0x3d, G: 0xbc, B: 0x74, A: 0xff},
-        drawing.Color{R: 0x3e, G: 0xbd, B: 0x73, A: 0xff},
-        drawing.Color{R: 0x40, G: 0xbe, B: 0x72, A: 0xff},
-        drawing.Color{R: 0x42, G: 0xbe, B: 0x71, A: 0xff},
-        drawing.Color{R: 0x44, G: 0xbf, B: 0x70, A: 0xff},
-        drawing.Color{R: 0x46, G: 0xc0, B: 0x6f, A: 0xff},
-        drawing.Color{R: 0x48, G: 0xc1, B: 0x6e, A: 0xff},
-        drawing.Color{R: 0x49, G: 0xc2, B: 0x6d, A: 0xff},
-        drawing.Color{R: 0x4b, G: 0xc2, B: 0x6c, A: 0xff},
-        drawing.Color{R: 0x4d, G: 0xc3, B: 0x6b, A: 0xff},
-        drawing.Color{R: 0x4f, G: 0xc4, B: 0x6a, A: 0xff},
-        drawing.Color{R: 0x51, G: 0xc5, B: 0x69, A: 0xff},
-        drawing.Color{R: 0x53, G: 0xc6, B: 0x68, A: 0xff},
-        drawing.Color{R: 0x55, G: 0xc6, B: 0x66, A: 0xff},
-        drawing.Color{R: 0x58, G: 0xc7, B: 0x65, A: 0xff},
-        drawing.Color{R: 0x5a, G: 0xc8, B: 0x64, A: 0xff},
-        drawing.Color{R: 0x5c, G: 0xc9, B: 0x63, A: 0xff},
-        drawing.Color{R: 0x5e, G: 0xc9, B: 0x62, A: 0xff},
-        drawing.Color{R: 0x60, G: 0xca, B: 0x60, A: 0xff},
-        drawing.Color{R: 0x62, G: 0xcb, B: 0x5f, A: 0xff},
-        drawing.Color{R: 0x65, G: 0xcc, B: 0x5e, A: 0xff},
-        drawing.Color{R: 0x67, G: 0xcc, B: 0x5c, A: 0xff},
-        drawing.Color{R: 0x69, G: 0xcd, B: 0x5b, A: 0xff},
-        drawing.Color{R: 0x6c, G: 0xce, B: 0x5a, A: 0xff},
-        drawing.Color{R: 0x6e, G: 0xce, B: 0x58, A: 0xff},
-        drawing.Color{R: 0x70, G: 0xcf, B: 0x57, A: 0xff},
-        drawing.Color{R: 0x73, G: 0xd0, B: 0x55, A: 0xff},
-        drawing.Color{R: 0x75, G: 0xd0, B: 0x54, A: 0xff},
-        drawing.Color{R: 0x77, G: 0xd1, B: 0x52, A: 0xff},
-        drawing.Color{R: 0x7a, G: 0xd2, B: 0x51, A: 0xff},
-        drawing.Color{R: 0x7c, G: 0xd2, B: 0x4f, A: 0xff},
-        drawing.Color{R: 0x7f, G: 0xd3, B: 0x4e, A: 0xff},
-        drawing.Color{R: 0x81, G: 0xd4, B: 0x4c, A: 0xff},
-        drawing.Color{R: 0x84, G: 0xd4, B: 0x4b, A: 0xff},
-        drawing.Color{R: 0x86, G: 0xd5, B: 0x49, A: 0xff},
-        drawing.Color{R: 0x89, G: 0xd5, B: 0x48, A: 0xff},
-        drawing.Color{R: 0x8b, G: 0xd6, B: 0x46, A: 0xff},
-        drawing.Color{R: 0x8e, G: 0xd7, B: 0x44, A: 0xff},
-        drawing.Color{R: 0x90, G: 0xd7, B: 0x43, A: 0xff},
-        drawing.Color{R: 0x93, G: 0xd8, B: 0x41, A: 0xff},
-        drawing.Color{R: 0x95, G: 0xd8, B: 0x3f, A: 0xff},
-        drawing.Color{R: 0x98, G: 0xd9, B: 0x3e, A: 0xff},
-        drawing.Color{R: 0x9b, G: 0xd9, B: 0x3c, A: 0xff},
-        drawing.Color{R: 0x9d, G: 0xda, B: 0x3a, A: 0xff},
-        drawing.Color{R: 0xa0, G: 0xda, B: 0x39, A: 0xff},
-        drawing.Color{R: 0xa3, G: 0xdb, B: 0x37, A: 0xff},
-        drawing.Color{R: 0xa5, G: 0xdb, B: 0x35, A: 0xff},
-        drawing.Color{R: 0xa8, G: 0xdc, B: 0x33, A: 0xff},
-        drawing.Color{R: 0xab, G: 0xdc, B: 0x32, A: 0xff},
-        drawing.Color{R: 0xad, G: 0xdd, B: 0x30, A: 0xff},
-        drawing.Color{R: 0xb0, G: 0xdd, B: 0x2e, A: 0xff},
-        drawing.Color{R: 0xb3, G: 0xdd, B: 0x2d, A: 0xff},
-        drawing.Color{R: 0xb5, G: 0xde, B: 0x2b, A: 0xff},
-        drawing.Color{R: 0xb8, G: 0xde, B: 0x29, A: 0xff},
-        drawing.Color{R: 0xbb, G: 0xdf, B: 0x27, A: 0xff},
-        drawing.Color{R: 0xbd, G: 0xdf, B: 0x26, A: 0xff},
-        drawing.Color{R: 0xc0, G: 0xdf, B: 0x24, A: 0xff},
-        drawing.Color{R: 0xc3, G: 0xe0, B: 0x23, A: 0xff},
-        drawing.Color{R: 0xc5, G: 0xe0, B: 0x21, A: 0xff},
-        drawing.Color{R: 0xc8, G: 0xe1, B: 0x20, A: 0xff},
-        drawing.Color{R: 0xcb, G: 0xe1, B: 0x1e, A: 0xff},
-        drawing.Color{R: 0xcd, G: 0xe1, B: 0x1d, A: 0xff},
-        drawing.Color{R: 0xd0, G: 0xe2, B: 0x1c, A: 0xff},
-        drawing.Color{R: 0xd3, G: 0xe2, B: 0x1b, A: 0xff},
-        drawing.Color{R: 0xd5, G: 0xe2, B: 0x1a, A: 0xff},
-        drawing.Color{R: 0xd8, G: 0xe3, B: 0x19, A: 0xff},
-        drawing.Color{R: 0xdb, G: 0xe3, B: 0x18, A: 0xff},
-        drawing.Color{R: 0xdd, G: 0xe3, B: 0x18, A: 0xff},
-        drawing.Color{R: 0xe0, G: 0xe4, B: 0x18, A: 0xff},
-        drawing.Color{R: 0xe2, G: 0xe4, B: 0x18, A: 0xff},
-        drawing.Color{R: 0xe5, G: 0xe4, B: 0x18, A: 0xff},
-        drawing.Color{R: 0xe8, G: 0xe5, B: 0x19, A: 0xff},
-        drawing.Color{R: 0xea, G: 0xe5, B: 0x19, A: 0xff},
-        drawing.Color{R: 0xed, G: 0xe5, B: 0x1a, A: 0xff},
-        drawing.Color{R: 0xef, G: 0xe6, B: 0x1b, A: 0xff},
-        drawing.Color{R: 0xf2, G: 0xe6, B: 0x1c, A: 0xff},
-        drawing.Color{R: 0xf4, G: 0xe6, B: 0x1e, A: 0xff},
-        drawing.Color{R: 0xf7, G: 0xe6, B: 0x1f, A: 0xff},
-        drawing.Color{R: 0xf9, G: 0xe7, B: 0x21, A: 0xff},
-        drawing.Color{R: 0xfb, G: 0xe7, B: 0x23, A: 0xff},
-        drawing.Color{R: 0xfe, G: 0xe7, B: 0x24, A: 0xff},
-}
-
-// Viridis creates a color map provider.
-func Viridis(v, vmin, vmax float64) drawing.Color <span class="cov0" title="0">{
-        normalized := (v - vmin) / (vmax - vmin)
-        index := uint8(normalized * 255)
-        return viridisColors[index]
-}</span>
-</pre>
-		
-		<pre class="file" id="file69" style="display: none">package chart
-
-import (
-        "math"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// XAxis represents the horizontal axis.
-type XAxis struct {
-        Name      string
-        NameStyle Style
-
-        Style          Style
-        ValueFormatter ValueFormatter
-        Range          Range
-
-        TickStyle    Style
-        Ticks        []Tick
-        TickPosition TickPosition
-
-        GridLines      []GridLine
-        GridMajorStyle Style
-        GridMinorStyle Style
-}
-
-// GetName returns the name.
-func (xa XAxis) GetName() string <span class="cov0" title="0">{
-        return xa.Name
-}</span>
-
-// GetStyle returns the style.
-func (xa XAxis) GetStyle() Style <span class="cov0" title="0">{
-        return xa.Style
-}</span>
-
-// GetValueFormatter returns the value formatter for the axis.
-func (xa XAxis) GetValueFormatter() ValueFormatter <span class="cov0" title="0">{
-        if xa.ValueFormatter != nil </span><span class="cov0" title="0">{
-                return xa.ValueFormatter
-        }</span>
-        <span class="cov0" title="0">return FloatValueFormatter</span>
-}
-
-// GetTickPosition returns the tick position option for the axis.
-func (xa XAxis) GetTickPosition(defaults ...TickPosition) TickPosition <span class="cov8" title="1">{
-        if xa.TickPosition == TickPositionUnset </span><span class="cov8" title="1">{
-                if len(defaults) &gt; 0 </span><span class="cov0" title="0">{
-                        return defaults[0]
-                }</span>
-                <span class="cov8" title="1">return TickPositionUnderTick</span>
-        }
-        <span class="cov0" title="0">return xa.TickPosition</span>
-}
-
-// GetTicks returns the ticks for a series.
-// The coalesce priority is:
-//         - User Supplied Ticks (i.e. Ticks array on the axis itself).
-//         - Range ticks (i.e. if the range provides ticks).
-//        - Generating continuous ticks based on minimum spacing and canvas width.
-func (xa XAxis) GetTicks(r Renderer, ra Range, defaults Style, vf ValueFormatter) []Tick <span class="cov8" title="1">{
-        if len(xa.Ticks) &gt; 0 </span><span class="cov8" title="1">{
-                return xa.Ticks
-        }</span>
-        <span class="cov8" title="1">if tp, isTickProvider := ra.(TicksProvider); isTickProvider </span><span class="cov0" title="0">{
-                return tp.GetTicks(r, defaults, vf)
-        }</span>
-        <span class="cov8" title="1">tickStyle := xa.Style.InheritFrom(defaults)
-        return GenerateContinuousTicks(r, ra, false, tickStyle, vf)</span>
-}
-
-// GetGridLines returns the gridlines for the axis.
-func (xa XAxis) GetGridLines(ticks []Tick) []GridLine <span class="cov0" title="0">{
-        if len(xa.GridLines) &gt; 0 </span><span class="cov0" title="0">{
-                return xa.GridLines
-        }</span>
-        <span class="cov0" title="0">return GenerateGridLines(ticks, xa.GridMajorStyle, xa.GridMinorStyle)</span>
-}
-
-// Measure returns the bounds of the axis.
-func (xa XAxis) Measure(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) Box <span class="cov8" title="1">{
-        tickStyle := xa.TickStyle.InheritFrom(xa.Style.InheritFrom(defaults))
-
-        tp := xa.GetTickPosition()
-
-        var ltx, rtx int
-        var tx, ty int
-        var left, right, bottom = math.MaxInt32, 0, 0
-        for index, t := range ticks </span><span class="cov8" title="1">{
-                v := t.Value
-                tb := Draw.MeasureText(r, t.Label, tickStyle.GetTextOptions())
-
-                tx = canvasBox.Left + ra.Translate(v)
-                ty = canvasBox.Bottom + DefaultXAxisMargin + tb.Height()
-                switch tp </span>{
-                case TickPositionUnderTick, TickPositionUnset:<span class="cov8" title="1">
-                        ltx = tx - tb.Width()&gt;&gt;1
-                        rtx = tx + tb.Width()&gt;&gt;1
-                        break</span>
-                case TickPositionBetweenTicks:<span class="cov0" title="0">
-                        if index &gt; 0 </span><span class="cov0" title="0">{
-                                ltx = ra.Translate(ticks[index-1].Value)
-                                rtx = tx
-                        }</span>
-                        <span class="cov0" title="0">break</span>
-                }
-
-                <span class="cov8" title="1">left = util.Math.MinInt(left, ltx)
-                right = util.Math.MaxInt(right, rtx)
-                bottom = util.Math.MaxInt(bottom, ty)</span>
-        }
-
-        <span class="cov8" title="1">if xa.NameStyle.Show &amp;&amp; len(xa.Name) &gt; 0 </span><span class="cov0" title="0">{
-                tb := Draw.MeasureText(r, xa.Name, xa.NameStyle.InheritFrom(defaults))
-                bottom += DefaultXAxisMargin + tb.Height()
-        }</span>
-
-        <span class="cov8" title="1">return Box{
-                Top:    canvasBox.Bottom,
-                Left:   left,
-                Right:  right,
-                Bottom: bottom,
-        }</span>
-}
-
-// Render renders the axis
-func (xa XAxis) Render(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) <span class="cov8" title="1">{
-        tickStyle := xa.TickStyle.InheritFrom(xa.Style.InheritFrom(defaults))
-
-        tickStyle.GetStrokeOptions().WriteToRenderer(r)
-        r.MoveTo(canvasBox.Left, canvasBox.Bottom)
-        r.LineTo(canvasBox.Right, canvasBox.Bottom)
-        r.Stroke()
-
-        tp := xa.GetTickPosition()
-
-        var tx, ty int
-        var maxTextHeight int
-        for index, t := range ticks </span><span class="cov8" title="1">{
-                v := t.Value
-                lx := ra.Translate(v)
-
-                tx = canvasBox.Left + lx
-
-                tickStyle.GetStrokeOptions().WriteToRenderer(r)
-                r.MoveTo(tx, canvasBox.Bottom)
-                r.LineTo(tx, canvasBox.Bottom+DefaultVerticalTickHeight)
-                r.Stroke()
-
-                tickWithAxisStyle := xa.TickStyle.InheritFrom(xa.Style.InheritFrom(defaults))
-                tb := Draw.MeasureText(r, t.Label, tickWithAxisStyle)
-
-                switch tp </span>{
-                case TickPositionUnderTick, TickPositionUnset:<span class="cov8" title="1">
-                        if tickStyle.TextRotationDegrees == 0 </span><span class="cov8" title="1">{
-                                tx = tx - tb.Width()&gt;&gt;1
-                                ty = canvasBox.Bottom + DefaultXAxisMargin + tb.Height()
-                        }</span> else<span class="cov0" title="0"> {
-                                ty = canvasBox.Bottom + (2 * DefaultXAxisMargin)
-                        }</span>
-                        <span class="cov8" title="1">Draw.Text(r, t.Label, tx, ty, tickWithAxisStyle)
-                        maxTextHeight = util.Math.MaxInt(maxTextHeight, tb.Height())
-                        break</span>
-                case TickPositionBetweenTicks:<span class="cov0" title="0">
-                        if index &gt; 0 </span><span class="cov0" title="0">{
-                                llx := ra.Translate(ticks[index-1].Value)
-                                ltx := canvasBox.Left + llx
-                                finalTickStyle := tickWithAxisStyle.InheritFrom(Style{TextHorizontalAlign: TextHorizontalAlignCenter})
-
-                                Draw.TextWithin(r, t.Label, Box{
-                                        Left:   ltx,
-                                        Right:  tx,
-                                        Top:    canvasBox.Bottom + DefaultXAxisMargin,
-                                        Bottom: canvasBox.Bottom + DefaultXAxisMargin,
-                                }, finalTickStyle)
-
-                                ftb := Text.MeasureLines(r, Text.WrapFit(r, t.Label, tx-ltx, finalTickStyle), finalTickStyle)
-                                maxTextHeight = util.Math.MaxInt(maxTextHeight, ftb.Height())
-                        }</span>
-                        <span class="cov0" title="0">break</span>
-                }
-        }
-
-        <span class="cov8" title="1">nameStyle := xa.NameStyle.InheritFrom(defaults)
-        if xa.NameStyle.Show &amp;&amp; len(xa.Name) &gt; 0 </span><span class="cov0" title="0">{
-                tb := Draw.MeasureText(r, xa.Name, nameStyle)
-                tx := canvasBox.Right - (canvasBox.Width()&gt;&gt;1 + tb.Width()&gt;&gt;1)
-                ty := canvasBox.Bottom + DefaultXAxisMargin + maxTextHeight + DefaultXAxisMargin + tb.Height()
-                Draw.Text(r, xa.Name, tx, ty, nameStyle)
-        }</span>
-
-        <span class="cov8" title="1">if xa.GridMajorStyle.Show || xa.GridMinorStyle.Show </span><span class="cov0" title="0">{
-                for _, gl := range xa.GetGridLines(ticks) </span><span class="cov0" title="0">{
-                        if (gl.IsMinor &amp;&amp; xa.GridMinorStyle.Show) || (!gl.IsMinor &amp;&amp; xa.GridMajorStyle.Show) </span><span class="cov0" title="0">{
-                                defaults := xa.GridMajorStyle
-                                if gl.IsMinor </span><span class="cov0" title="0">{
-                                        defaults = xa.GridMinorStyle
-                                }</span>
-                                <span class="cov0" title="0">gl.Render(r, canvasBox, ra, true, gl.Style.InheritFrom(defaults))</span>
-                        }
-                }
-        }
-}
-</pre>
-		
-		<pre class="file" id="file70" style="display: none">package chart
-
-import (
-        "math"
-
-        util "github.com/wcharczuk/go-chart/util"
-)
-
-// YAxis is a veritcal rule of the range.
-// There can be (2) y-axes; a primary and secondary.
-type YAxis struct {
-        Name      string
-        NameStyle Style
-
-        Style Style
-
-        Zero GridLine
-
-        AxisType  YAxisType
-        Ascending bool
-
-        ValueFormatter ValueFormatter
-        Range          Range
-
-        TickStyle Style
-        Ticks     []Tick
-
-        GridLines      []GridLine
-        GridMajorStyle Style
-        GridMinorStyle Style
-}
-
-// GetName returns the name.
-func (ya YAxis) GetName() string <span class="cov0" title="0">{
-        return ya.Name
-}</span>
-
-// GetNameStyle returns the name style.
-func (ya YAxis) GetNameStyle() Style <span class="cov0" title="0">{
-        return ya.NameStyle
-}</span>
-
-// GetStyle returns the style.
-func (ya YAxis) GetStyle() Style <span class="cov0" title="0">{
-        return ya.Style
-}</span>
-
-// GetValueFormatter returns the value formatter for the axis.
-func (ya YAxis) GetValueFormatter() ValueFormatter <span class="cov0" title="0">{
-        if ya.ValueFormatter != nil </span><span class="cov0" title="0">{
-                return ya.ValueFormatter
-        }</span>
-        <span class="cov0" title="0">return FloatValueFormatter</span>
-}
-
-// GetTickStyle returns the tick style.
-func (ya YAxis) GetTickStyle() Style <span class="cov0" title="0">{
-        return ya.TickStyle
-}</span>
-
-// GetTicks returns the ticks for a series.
-// The coalesce priority is:
-//         - User Supplied Ticks (i.e. Ticks array on the axis itself).
-//         - Range ticks (i.e. if the range provides ticks).
-//        - Generating continuous ticks based on minimum spacing and canvas width.
-func (ya YAxis) GetTicks(r Renderer, ra Range, defaults Style, vf ValueFormatter) []Tick <span class="cov8" title="1">{
-        if len(ya.Ticks) &gt; 0 </span><span class="cov8" title="1">{
-                return ya.Ticks
-        }</span>
-        <span class="cov8" title="1">if tp, isTickProvider := ra.(TicksProvider); isTickProvider </span><span class="cov0" title="0">{
-                return tp.GetTicks(r, defaults, vf)
-        }</span>
-        <span class="cov8" title="1">tickStyle := ya.Style.InheritFrom(defaults)
-        return GenerateContinuousTicks(r, ra, true, tickStyle, vf)</span>
-}
-
-// GetGridLines returns the gridlines for the axis.
-func (ya YAxis) GetGridLines(ticks []Tick) []GridLine <span class="cov0" title="0">{
-        if len(ya.GridLines) &gt; 0 </span><span class="cov0" title="0">{
-                return ya.GridLines
-        }</span>
-        <span class="cov0" title="0">return GenerateGridLines(ticks, ya.GridMajorStyle, ya.GridMinorStyle)</span>
-}
-
-// Measure returns the bounds of the axis.
-func (ya YAxis) Measure(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) Box <span class="cov8" title="1">{
-        var tx int
-        if ya.AxisType == YAxisPrimary </span><span class="cov8" title="1">{
-                tx = canvasBox.Right + DefaultYAxisMargin
-        }</span> else<span class="cov8" title="1"> if ya.AxisType == YAxisSecondary </span><span class="cov8" title="1">{
-                tx = canvasBox.Left - DefaultYAxisMargin
-        }</span>
-
-        <span class="cov8" title="1">ya.TickStyle.InheritFrom(ya.Style.InheritFrom(defaults)).WriteToRenderer(r)
-        var minx, maxx, miny, maxy = math.MaxInt32, 0, math.MaxInt32, 0
-        var maxTextHeight int
-        for _, t := range ticks </span><span class="cov8" title="1">{
-                v := t.Value
-                ly := canvasBox.Bottom - ra.Translate(v)
-
-                tb := r.MeasureText(t.Label)
-                tbh2 := tb.Height() &gt;&gt; 1
-                finalTextX := tx
-                if ya.AxisType == YAxisSecondary </span><span class="cov8" title="1">{
-                        finalTextX = tx - tb.Width()
-                }</span>
-
-                <span class="cov8" title="1">maxTextHeight = util.Math.MaxInt(tb.Height(), maxTextHeight)
-
-                if ya.AxisType == YAxisPrimary </span><span class="cov8" title="1">{
-                        minx = canvasBox.Right
-                        maxx = util.Math.MaxInt(maxx, tx+tb.Width())
-                }</span> else<span class="cov8" title="1"> if ya.AxisType == YAxisSecondary </span><span class="cov8" title="1">{
-                        minx = util.Math.MinInt(minx, finalTextX)
-                        maxx = util.Math.MaxInt(maxx, tx)
-                }</span>
-
-                <span class="cov8" title="1">miny = util.Math.MinInt(miny, ly-tbh2)
-                maxy = util.Math.MaxInt(maxy, ly+tbh2)</span>
-        }
-
-        <span class="cov8" title="1">if ya.NameStyle.Show &amp;&amp; len(ya.Name) &gt; 0 </span><span class="cov0" title="0">{
-                maxx += (DefaultYAxisMargin + maxTextHeight)
-        }</span>
-
-        <span class="cov8" title="1">return Box{
-                Top:    miny,
-                Left:   minx,
-                Right:  maxx,
-                Bottom: maxy,
-        }</span>
-}
-
-// Render renders the axis.
-func (ya YAxis) Render(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) <span class="cov8" title="1">{
-        tickStyle := ya.TickStyle.InheritFrom(ya.Style.InheritFrom(defaults))
-        tickStyle.WriteToRenderer(r)
-
-        sw := tickStyle.GetStrokeWidth(defaults.StrokeWidth)
-
-        var lx int
-        var tx int
-        if ya.AxisType == YAxisPrimary </span><span class="cov8" title="1">{
-                lx = canvasBox.Right + int(sw)
-                tx = lx + DefaultYAxisMargin
-        }</span> else<span class="cov0" title="0"> if ya.AxisType == YAxisSecondary </span><span class="cov0" title="0">{
-                lx = canvasBox.Left - int(sw)
-                tx = lx - DefaultYAxisMargin
-        }</span>
-
-        <span class="cov8" title="1">r.MoveTo(lx, canvasBox.Bottom)
-        r.LineTo(lx, canvasBox.Top)
-        r.Stroke()
-
-        var maxTextWidth int
-        var finalTextX, finalTextY int
-        for _, t := range ticks </span><span class="cov8" title="1">{
-                v := t.Value
-                ly := canvasBox.Bottom - ra.Translate(v)
-
-                tb := Draw.MeasureText(r, t.Label, tickStyle)
-
-                if tb.Width() &gt; maxTextWidth </span><span class="cov8" title="1">{
-                        maxTextWidth = tb.Width()
-                }</span>
-
-                <span class="cov8" title="1">if ya.AxisType == YAxisSecondary </span><span class="cov0" title="0">{
-                        finalTextX = tx - tb.Width()
-                }</span> else<span class="cov8" title="1"> {
-                        finalTextX = tx
-                }</span>
-
-                <span class="cov8" title="1">if tickStyle.TextRotationDegrees == 0 </span><span class="cov8" title="1">{
-                        finalTextY = ly + tb.Height()&gt;&gt;1
-                }</span> else<span class="cov0" title="0"> {
-                        finalTextY = ly
-                }</span>
-
-                <span class="cov8" title="1">tickStyle.WriteToRenderer(r)
-
-                r.MoveTo(lx, ly)
-                if ya.AxisType == YAxisPrimary </span><span class="cov8" title="1">{
-                        r.LineTo(lx+DefaultHorizontalTickWidth, ly)
-                }</span> else<span class="cov0" title="0"> if ya.AxisType == YAxisSecondary </span><span class="cov0" title="0">{
-                        r.LineTo(lx-DefaultHorizontalTickWidth, ly)
-                }</span>
-                <span class="cov8" title="1">r.Stroke()
-
-                Draw.Text(r, t.Label, finalTextX, finalTextY, tickStyle)</span>
-        }
-
-        <span class="cov8" title="1">nameStyle := ya.NameStyle.InheritFrom(defaults.InheritFrom(Style{TextRotationDegrees: 90}))
-        if ya.NameStyle.Show &amp;&amp; len(ya.Name) &gt; 0 </span><span class="cov0" title="0">{
-                nameStyle.GetTextOptions().WriteToRenderer(r)
-                tb := Draw.MeasureText(r, ya.Name, nameStyle)
-
-                var tx int
-                if ya.AxisType == YAxisPrimary </span><span class="cov0" title="0">{
-                        tx = canvasBox.Right + int(sw) + DefaultYAxisMargin + maxTextWidth + DefaultYAxisMargin
-                }</span> else<span class="cov0" title="0"> if ya.AxisType == YAxisSecondary </span><span class="cov0" title="0">{
-                        tx = canvasBox.Left - (DefaultYAxisMargin + int(sw) + maxTextWidth + DefaultYAxisMargin)
-                }</span>
-
-                <span class="cov0" title="0">var ty int
-                if nameStyle.TextRotationDegrees == 0 </span><span class="cov0" title="0">{
-                        ty = canvasBox.Top + (canvasBox.Height()&gt;&gt;1 - tb.Width()&gt;&gt;1)
-                }</span> else<span class="cov0" title="0"> {
-                        ty = canvasBox.Top + (canvasBox.Height()&gt;&gt;1 - tb.Height()&gt;&gt;1)
-                }</span>
-
-                <span class="cov0" title="0">Draw.Text(r, ya.Name, tx, ty, nameStyle)</span>
-        }
-
-        <span class="cov8" title="1">if ya.Zero.Style.Show </span><span class="cov0" title="0">{
-                ya.Zero.Render(r, canvasBox, ra, false, Style{})
-        }</span>
-
-        <span class="cov8" title="1">if ya.GridMajorStyle.Show || ya.GridMinorStyle.Show </span><span class="cov0" title="0">{
-                for _, gl := range ya.GetGridLines(ticks) </span><span class="cov0" title="0">{
-                        if (gl.IsMinor &amp;&amp; ya.GridMinorStyle.Show) || (!gl.IsMinor &amp;&amp; ya.GridMajorStyle.Show) </span><span class="cov0" title="0">{
-                                defaults := ya.GridMajorStyle
-                                if gl.IsMinor </span><span class="cov0" title="0">{
-                                        defaults = ya.GridMinorStyle
-                                }</span>
-                                <span class="cov0" title="0">gl.Render(r, canvasBox, ra, false, gl.Style.InheritFrom(defaults))</span>
-                        }
-                }
-        }
-}
-</pre>
-		
-		</div>
-	</body>
-	<script>
-	(function() {
-		var files = document.getElementById('files');
-		var visible;
-		files.addEventListener('change', onChange, false);
-		function select(part) {
-			if (visible)
-				visible.style.display = 'none';
-			visible = document.getElementById(part);
-			if (!visible)
-				return;
-			files.value = part;
-			visible.style.display = 'block';
-			location.hash = part;
-		}
-		function onChange() {
-			select(files.value);
-			window.scrollTo(0, 0);
-		}
-		if (location.hash != "") {
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-			select("file0");
-		}
-	})();
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