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Helper API refactor (#40)

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* api cleaup

* updates

* wtf

* updates

* snapshot.

* tweaks

* snapshot

* api tweaks.

* updates

* updates

* updates

* changes.

* updates

* updates

* sequence => seq

* dont need to use curl, just using wget

* fixing examples
This commit is contained in:
Will Charczuk 2017-05-12 17:12:23 -07:00 • committed by GitHub
parent 43212f871f
commit 03708a90ef
100 changed files with 1687 additions and 1055 deletions
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68
bollinger_band_series.go
View file

@ -2,7 +2,8 @@ package chart
import (
"fmt"
"math"
"github.com/wcharczuk/go-chart/seq"
)
// BollingerBandsSeries draws bollinger bands for an inner series.
@ -14,9 +15,9 @@ type BollingerBandsSeries struct {
Period int
K float64
InnerSeries ValueProvider
InnerSeries ValuesProvider
valueBuffer *RingBuffer
valueBuffer *seq.Buffer
}
// GetName returns the name of the time series.
@ -42,7 +43,9 @@ func (bbs BollingerBandsSeries) GetPeriod() int {
return bbs.Period
}
// GetK returns the K value.
// 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 {
if bbs.K == 0 {
if len(defaults) > 0 {
@ -54,35 +57,35 @@ func (bbs BollingerBandsSeries) GetK(defaults ...float64) float64 {
}
// Len returns the number of elements in the series.
func (bbs *BollingerBandsSeries) Len() int {
func (bbs BollingerBandsSeries) Len() int {
return bbs.InnerSeries.Len()
}
// GetBoundedValue gets the bounded value for the series.
func (bbs *BollingerBandsSeries) GetBoundedValue(index int) (x, y1, y2 float64) {
// GetBoundedValues gets the bounded value for the series.
func (bbs *BollingerBandsSeries) GetBoundedValues(index int) (x, y1, y2 float64) {
if bbs.InnerSeries == nil {
return
}
if bbs.valueBuffer == nil || index == 0 {
bbs.valueBuffer = NewRingBufferWithCapacity(bbs.GetPeriod())
bbs.valueBuffer = seq.NewBufferWithCapacity(bbs.GetPeriod())
}
if bbs.valueBuffer.Len() >= bbs.GetPeriod() {
bbs.valueBuffer.Dequeue()
}
px, py := bbs.InnerSeries.GetValue(index)
px, py := bbs.InnerSeries.GetValues(index)
bbs.valueBuffer.Enqueue(py)
x = px
ay := bbs.getAverage(bbs.valueBuffer)
std := bbs.getStdDev(bbs.valueBuffer)
ay := seq.New(bbs.valueBuffer).Average()
std := seq.New(bbs.valueBuffer).StdDev()
y1 = ay + (bbs.GetK() * std)
y2 = ay - (bbs.GetK() * std)
return
}
// GetBoundedLastValue returns the last bounded value for the series.
func (bbs *BollingerBandsSeries) GetBoundedLastValue() (x, y1, y2 float64) {
// GetBoundedLastValues returns the last bounded value for the series.
func (bbs *BollingerBandsSeries) GetBoundedLastValues() (x, y1, y2 float64) {
if bbs.InnerSeries == nil {
return
}
@ -93,15 +96,15 @@ func (bbs *BollingerBandsSeries) GetBoundedLastValue() (x, y1, y2 float64) {
startAt = 0
}
vb := NewRingBufferWithCapacity(period)
vb := seq.NewBufferWithCapacity(period)
for index := startAt; index < seriesLength; index++ {
xn, yn := bbs.InnerSeries.GetValue(index)
xn, yn := bbs.InnerSeries.GetValues(index)
vb.Enqueue(yn)
x = xn
}
ay := bbs.getAverage(vb)
std := bbs.getStdDev(vb)
ay := seq.Seq{Provider: vb}.Average()
std := seq.Seq{Provider: vb}.StdDev()
y1 = ay + (bbs.GetK() * std)
y2 = ay - (bbs.GetK() * std)
@ -120,37 +123,6 @@ func (bbs *BollingerBandsSeries) Render(r Renderer, canvasBox Box, xrange, yrang
Draw.BoundedSeries(r, canvasBox, xrange, yrange, s, bbs, bbs.GetPeriod())
}
func (bbs BollingerBandsSeries) getAverage(valueBuffer *RingBuffer) float64 {
var accum float64
valueBuffer.Each(func(v interface{}) {
if typed, isTyped := v.(float64); isTyped {
accum += typed
}
})
return accum / float64(valueBuffer.Len())
}
func (bbs BollingerBandsSeries) getVariance(valueBuffer *RingBuffer) float64 {
if valueBuffer.Len() == 0 {
return 0
}
var variance float64
m := bbs.getAverage(valueBuffer)
valueBuffer.Each(func(v interface{}) {
if n, isTyped := v.(float64); isTyped {
variance += (float64(n) - m) * (float64(n) - m)
}
})
return variance / float64(valueBuffer.Len())
}
func (bbs BollingerBandsSeries) getStdDev(valueBuffer *RingBuffer) float64 {
return math.Pow(bbs.getVariance(valueBuffer), 0.5)
}
// Validate validates the series.
func (bbs BollingerBandsSeries) Validate() error {
if bbs.InnerSeries == nil {