go-chart/_examples/timeseries/main.go
2018-12-06 16:46:27 +01:00

84 lines
2.3 KiB
Go

package main
import (
"net/http"
"time"
"git.gutmet.org/go-chart.git"
)
func drawChart(res http.ResponseWriter, req *http.Request) {
/*
This is an example of using the `TimeSeries` to automatically coerce time.Time values into a continuous xrange.
Note: chart.TimeSeries implements `ValueFormatterProvider` and as a result gives the XAxis the appropriate formatter to use for the ticks.
*/
graph := chart.Chart{
XAxis: chart.XAxis{
Style: chart.StyleShow(),
},
Series: []chart.Series{
chart.TimeSeries{
XValues: []time.Time{
time.Now().AddDate(0, 0, -10),
time.Now().AddDate(0, 0, -9),
time.Now().AddDate(0, 0, -8),
time.Now().AddDate(0, 0, -7),
time.Now().AddDate(0, 0, -6),
time.Now().AddDate(0, 0, -5),
time.Now().AddDate(0, 0, -4),
time.Now().AddDate(0, 0, -3),
time.Now().AddDate(0, 0, -2),
time.Now().AddDate(0, 0, -1),
time.Now(),
},
YValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0},
},
},
}
res.Header().Set("Content-Type", "image/png")
graph.Render(chart.PNG, res)
}
func drawCustomChart(res http.ResponseWriter, req *http.Request) {
/*
This is basically the other timeseries example, except we switch to hour intervals and specify a different formatter from default for the xaxis tick labels.
*/
graph := chart.Chart{
XAxis: chart.XAxis{
Style: chart.StyleShow(),
ValueFormatter: chart.TimeHourValueFormatter,
},
Series: []chart.Series{
chart.TimeSeries{
XValues: []time.Time{
time.Now().Add(-10 * time.Hour),
time.Now().Add(-9 * time.Hour),
time.Now().Add(-8 * time.Hour),
time.Now().Add(-7 * time.Hour),
time.Now().Add(-6 * time.Hour),
time.Now().Add(-5 * time.Hour),
time.Now().Add(-4 * time.Hour),
time.Now().Add(-3 * time.Hour),
time.Now().Add(-2 * time.Hour),
time.Now().Add(-1 * time.Hour),
time.Now(),
},
YValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0},
},
},
}
res.Header().Set("Content-Type", "image/png")
graph.Render(chart.PNG, res)
}
func main() {
http.HandleFunc("/", drawChart)
http.HandleFunc("/favicon.ico", func(res http.ResponseWriter, req *http.Request) {
res.Write([]byte{})
})
http.HandleFunc("/custom", drawCustomChart)
http.ListenAndServe(":8080", nil)
}