go-chart/_examples/twoaxis/main.go
2017-02-03 10:47:48 -08:00

61 lines
1.5 KiB
Go

package main
import (
"fmt"
"net/http"
"github.com/wcharczuk/go-chart"
)
func drawChart(res http.ResponseWriter, req *http.Request) {
/*
In this example we add a second series, and assign it to the secondary y axis, giving that series it's own range.
We also enable all of the axes by setting the `Show` propery of their respective styles to `true`.
*/
graph := chart.Chart{
XAxis: chart.XAxis{
Style: chart.Style{
Show: true, //enables / displays the x-axis
},
TickPosition: chart.TickPositionBetweenTicks,
ValueFormatter: func(v interface{}) string {
typed := v.(float64)
typedDate := chart.Time.FromFloat64(typed)
return fmt.Sprintf("%d-%d\n%d", typedDate.Month(), typedDate.Day(), typedDate.Year())
},
},
YAxis: chart.YAxis{
Style: chart.Style{
Show: true, //enables / displays the y-axis
},
},
YAxisSecondary: chart.YAxis{
Style: chart.Style{
Show: true, //enables / displays the secondary y-axis
},
},
Series: []chart.Series{
chart.ContinuousSeries{
XValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0},
YValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0},
},
chart.ContinuousSeries{
YAxis: chart.YAxisSecondary,
XValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0},
YValues: []float64{50.0, 40.0, 30.0, 20.0, 10.0},
},
},
}
res.Header().Set("Content-Type", "image/png")
graph.Render(chart.PNG, res)
}
func main() {
http.HandleFunc("/", drawChart)
http.ListenAndServe(":8080", nil)
}