adding validation.

_examples/twopoint/main.go

@@ -0,0 +1,72 @@
+package main
+
+import (
+	"bytes"
+	"log"
+	"os"
+	//"time"
+	"github.com/wcharczuk/go-chart" //exposes "chart"
+)
+
+func main() {
+
+	var b float64
+	b = 1000
+
+	ts1 := chart.ContinuousSeries{ //TimeSeries{
+		Name: "Time Series",
+		Style: chart.Style{
+			Show: true,
+		},
+
+		//XValues: []time.Time{time.Unix(3*b,0),time.Unix(4*b,0),time.Unix(5*b,0),time.Unix(6*b,0),time.Unix(7*b,0),time.Unix(8*b,0),time.Unix(9*b,0),time.Unix(10*b,0)},
+		XValues: []float64{10 * b, 20 * b, 30 * b, 40 * b, 50 * b, 60 * b, 70 * b, 80 * b},
+		YValues: []float64{1.0, 2.0, 30.0, 4.0, 50.0, 6.0, 7.0, 88.0},
+	}
+
+	ts2 := chart.ContinuousSeries{ //TimeSeries{
+		Style: chart.Style{
+			Show:        true,
+			StrokeColor: chart.GetDefaultColor(1),
+		},
+
+		XValues: []float64{10 * b, 20 * b, 30 * b, 40 * b, 50 * b, 60 * b, 70 * b, 80 * b},
+		YValues: []float64{15.0, 52.0, 30.0, 42.0, 50.0, 26.0, 77.0, 38.0},
+	}
+
+	graph := chart.Chart{
+
+		XAxis: chart.XAxis{
+			Name:           "The XAxis",
+			NameStyle:      chart.StyleShow(),
+			Style:          chart.StyleShow(),
+			ValueFormatter: chart.TimeMinuteValueFormatter, //TimeHourValueFormatter,
+		},
+
+		YAxis: chart.YAxis{
+			Name:      "The YAxis",
+			NameStyle: chart.StyleShow(),
+			Style:     chart.StyleShow(),
+		},
+
+		Series: []chart.Series{
+			ts1,
+			ts2,
+		},
+	}
+
+	buffer := bytes.NewBuffer([]byte{})
+	err := graph.Render(chart.PNG, buffer)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fo, err := os.Create("output.png")
+	if err != nil {
+		panic(err)
+	}
+
+	if _, err := fo.Write(buffer.Bytes()); err != nil {
+		panic(err)
+	}
+}