// Example_errBars draws points and error bars.
func Example_errBars() *plot.Plot {
type errPoints struct {
plotter.XYs
plotter.YErrors
plotter.XErrors
}
rand.Seed(int64(0))
n := 15
data := errPoints{
XYs: randomPoints(n),
YErrors: plotter.YErrors(randomError(n)),
XErrors: plotter.XErrors(randomError(n)),
}
p, err := plot.New()
if err != nil {
panic(err)
}
scatter := must(plotter.NewScatter(data)).(*plotter.Scatter)
scatter.Shape = draw.CrossGlyph{}
xerrs, err := plotter.NewXErrorBars(data)
if err != nil {
panic(err)
}
yerrs, err := plotter.NewYErrorBars(data)
if err != nil {
panic(err)
}
p.Add(scatter, xerrs, yerrs)
p.Add(plotter.NewGlyphBoxes())
return p
}
// AddYErrorBars adds YErrorBars to a plot.
// The variadic arguments must be
// of type plotter.XYer, and plotter.YErrorer.
// Each errorer is added to the plot the color from
// the Colors function corresponding to its position
// in the argument list.
//
// If an error occurs then none of the plotters are added
// to the plot, and the error is returned.
func AddYErrorBars(plt *plot.Plot, es ...interface {
plotter.XYer
plotter.YErrorer
}) error {
var ps []plot.Plotter
for i, e := range es {
bars, err := plotter.NewYErrorBars(e)
if err != nil {
return err
}
bars.Color = Color(i)
ps = append(ps, bars)
}
plt.Add(ps...)
return nil
}
// AddErrorBars adds XErrorBars and YErrorBars
// to a plot. The variadic arguments must be
// of type plotter.XYer, and must be either a
// plotter.XErrorer, plotter.YErrorer, or both.
// Each errorer is added to the plot the color from
// the Colors function corresponding to its position
// in the argument list.
//
// If an error occurs then none of the plotters are added
// to the plot, and the error is returned.
func AddErrorBars(plt *plot.Plot, vs ...interface{}) error {
var ps []plot.Plotter
for i, v := range vs {
added := false
if xerr, ok := v.(interface {
plotter.XYer
plotter.XErrorer
}); ok {
e, err := plotter.NewXErrorBars(xerr)
if err != nil {
return err
}
e.Color = Color(i)
ps = append(ps, e)
added = true
}
if yerr, ok := v.(interface {
plotter.XYer
plotter.YErrorer
}); ok {
e, err := plotter.NewYErrorBars(yerr)
if err != nil {
return err
}
e.Color = Color(i)
ps = append(ps, e)
added = true
}
if added {
continue
}
panic(fmt.Sprintf("AddErrorBars expects plotter.XErrorer or plotter.YErrorer, got %T", v))
}
plt.Add(ps...)
return nil
}