Method Plot

plotter/boxplot.go:332–380

(c draw.Canvas, plt *plot.Plot)

type horizBoxPlot struct{ *BoxPlot }

func (b horizBoxPlot) Plot(c draw.Canvas, plt *plot.Plot) {
	trX, trY := plt.Transforms(&c)
	y := trY(b.Location)
	if !c.ContainsY(y) {
		return
	}
	y += b.Offset

	med := trX(b.Median)
	q1 := trX(b.Quartile1)
	q3 := trX(b.Quartile3)
	aLow := trX(b.AdjLow)
	aHigh := trX(b.AdjHigh)

	pts := []vg.Point{
		{X: q1, Y: y - b.Width/2},
		{X: q3, Y: y - b.Width/2},
		{X: q3, Y: y + b.Width/2},
		{X: q1, Y: y + b.Width/2},
		{X: q1, Y: y - b.Width/2 - b.BoxStyle.Width/2},
	}
	box := c.ClipLinesX(pts)
	if b.FillColor != nil {
		c.FillPolygon(b.FillColor, c.ClipPolygonX(pts))
	}
	c.StrokeLines(b.BoxStyle, box...)

	medLine := c.ClipLinesX([]vg.Point{
		{X: med, Y: y - b.Width/2},
		{X: med, Y: y + b.Width/2},
	})
	c.StrokeLines(b.MedianStyle, medLine...)

	cap := b.CapWidth / 2
	whisks := c.ClipLinesX(
		[]vg.Point{{X: q3, Y: y}, {X: aHigh, Y: y}},
		[]vg.Point{{X: aHigh, Y: y - cap}, {X: aHigh, Y: y + cap}},
		[]vg.Point{{X: q1, Y: y}, {X: aLow, Y: y}},
		[]vg.Point{{X: aLow, Y: y - cap}, {X: aLow, Y: y + cap}},
	)
	c.StrokeLines(b.WhiskerStyle, whisks...)

	for _, out := range b.Outside {
		x := trX(b.Value(out))
		if c.ContainsX(x) {
			c.DrawGlyphNoClip(b.GlyphStyle, vg.Point{X: x, Y: y})
		}
	}
}

// DataRange returns the minimum and maximum x
// and y values, implementing the plot.DataRanger