go-chart/_examples/custom_ranges/main.go

package main

import (
	"net/http"

	chart "github.com/wcharczuk/go-chart"
)

func drawChart(res http.ResponseWriter, req *http.Request) {
	/*
	   In this example we set a custom range for the y-axis, overriding the automatic range generation.
	   Note: the chart will still generate the ticks automatically based on the custom range, so the intervals may be a bit weird.
	*/

	graph := chart.Chart{
		YAxis: chart.YAxis{
			Style: chart.StyleShow(),
			Range: &chart.ContinuousRange{
				Min: 0.0,
				Max: 10.0,
			},
		},
		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},
			},
		},
	}

	res.Header().Set("Content-Type", "image/png")
	graph.Render(chart.PNG, res)
}

func main() {
	http.HandleFunc("/", drawChart)
	http.ListenAndServe(":8080", nil)
}