Golang vg.Points函数代码示例

// Example_groupedHorizontalBoxPlots draws vertical boxplots.
func Example_groupedHorizontalBoxPlots() *plot.Plot {
	rand.Seed(int64(0))
	n := 100
	uniform := make(plotter.Values, n)
	normal := make(plotter.Values, n)
	expon := make(plotter.Values, n)
	for i := 0; i < n; i++ {
		uniform[i] = rand.Float64()
		normal[i] = rand.NormFloat64()
		expon[i] = rand.ExpFloat64()
	}

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Box Plot"
	p.Y.Label.Text = "plotter.Values"

	w := vg.Points(20)
	for y := 0.0; y < 3.0; y++ {
		b0 := must(plotter.MakeHorizBoxPlot(w, y, uniform)).(plotter.HorizBoxPlot)
		b0.Offset = -w - vg.Points(3)
		b1 := must(plotter.MakeHorizBoxPlot(w, y, normal)).(plotter.HorizBoxPlot)
		b2 := must(plotter.MakeHorizBoxPlot(w, y, expon)).(plotter.HorizBoxPlot)
		b2.Offset = w + vg.Points(3)
		p.Add(b0, b1, b2)
	}
	p.NominalY("Group 0", "Group 1", "Group 2")
	return p
}

// Example_groupedBoxPlots draws vertical boxplots.
func Example_groupedBoxPlots() *plot.Plot {
	rand.Seed(int64(0))
	n := 100
	uniform := make(plotter.Values, n)
	normal := make(plotter.Values, n)
	expon := make(plotter.Values, n)
	for i := 0; i < n; i++ {
		uniform[i] = rand.Float64()
		normal[i] = rand.NormFloat64()
		expon[i] = rand.ExpFloat64()
	}

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Box Plot"
	p.Y.Label.Text = "plotter.Values"

	w := vg.Points(20)
	for x := 0.0; x < 3.0; x++ {
		b0 := must(plotter.NewBoxPlot(w, x, uniform)).(*plotter.BoxPlot)
		b0.Offset = -w - vg.Points(3)
		b1 := must(plotter.NewBoxPlot(w, x, normal)).(*plotter.BoxPlot)
		b2 := must(plotter.NewBoxPlot(w, x, expon)).(*plotter.BoxPlot)
		b2.Offset = w + vg.Points(3)
		p.Add(b0, b1, b2)
	}

	// Set the X axis of the plot to nominal with
	// the given names for x=0, x=1 and x=2.
	p.NominalX("Group 0", "Group 1", "Group 2")
	return p
}

// Draw the plotinum logo.
func Example_logo() *plot.Plot {
	p, err := plot.New()
	if err != nil {
		panic(err)
	}

	plotter.DefaultLineStyle.Width = vg.Points(1)
	plotter.DefaultGlyphStyle.Radius = vg.Points(3)

	p.Y.Tick.Marker = plot.ConstantTicks([]plot.Tick{
		{0, "0"}, {0.25, ""}, {0.5, "0.5"}, {0.75, ""}, {1, "1"},
	})
	p.X.Tick.Marker = plot.ConstantTicks([]plot.Tick{
		{0, "0"}, {0.25, ""}, {0.5, "0.5"}, {0.75, ""}, {1, "1"},
	})

	pts := plotter.XYs{{0, 0}, {0, 1}, {0.5, 1}, {0.5, 0.6}, {0, 0.6}}
	line := must(plotter.NewLine(pts)).(*plotter.Line)
	scatter := must(plotter.NewScatter(pts)).(*plotter.Scatter)
	p.Add(line, scatter)

	pts = plotter.XYs{{1, 0}, {0.75, 0}, {0.75, 0.75}}
	line = must(plotter.NewLine(pts)).(*plotter.Line)
	scatter = must(plotter.NewScatter(pts)).(*plotter.Scatter)
	p.Add(line, scatter)

	pts = plotter.XYs{{0.5, 0.5}, {1, 0.5}}
	line = must(plotter.NewLine(pts)).(*plotter.Line)
	scatter = must(plotter.NewScatter(pts)).(*plotter.Scatter)
	p.Add(line, scatter)

	return p
}

// NewBoxPlot returns a new BoxPlot that represents
// the distribution of the given values.  The style of
// the box plot is that used for Tukey's schematic
// plots is ``Exploratory Data Analysis.''
//
// An error is returned if the boxplot is created with
// no values.
//
// The fence values are 1.5x the interquartile before
// the first quartile and after the third quartile.  Any
// value that is outside of the fences are drawn as
// Outside points.  The adjacent values (to which the
// whiskers stretch) are the minimum and maximum
// values that are not outside the fences.
func NewBoxPlot(w vg.Length, loc float64, values Valuer) (*BoxPlot, error) {
	if w < 0 {
		return nil, errors.New("Negative boxplot width")
	}

	b := new(BoxPlot)
	var err error
	if b.fiveStatPlot, err = newFiveStat(w, loc, values); err != nil {
		return nil, err
	}

	b.Width = w
	b.CapWidth = 3 * w / 4

	b.GlyphStyle = DefaultGlyphStyle
	b.BoxStyle = DefaultLineStyle
	b.MedianStyle = DefaultLineStyle
	b.WhiskerStyle = draw.LineStyle{
		Width:  vg.Points(0.5),
		Dashes: []vg.Length{vg.Points(4), vg.Points(2)},
	}

	if len(b.Values) == 0 {
		b.Width = 0
		b.GlyphStyle.Radius = 0
		b.BoxStyle.Width = 0
		b.MedianStyle.Width = 0
		b.WhiskerStyle.Width = 0
	}

	return b, nil
}

// Example_boxPlots draws vertical boxplots.
func Example_boxPlots() *plot.Plot {
	rand.Seed(int64(0))
	n := 100
	uniform := make(plotter.Values, n)
	normal := make(plotter.Values, n)
	expon := make(plotter.Values, n)
	for i := 0; i < n; i++ {
		uniform[i] = rand.Float64()
		normal[i] = rand.NormFloat64()
		expon[i] = rand.ExpFloat64()
	}

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Box Plot"
	p.Y.Label.Text = "plotter.Values"

	// Make boxes for our data and add them to the plot.
	p.Add(must(plotter.NewBoxPlot(vg.Points(20), 0, uniform)).(*plotter.BoxPlot),
		must(plotter.NewBoxPlot(vg.Points(20), 1, normal)).(*plotter.BoxPlot),
		must(plotter.NewBoxPlot(vg.Points(20), 2, expon)).(*plotter.BoxPlot))

	// Set the X axis of the plot to nominal with
	// the given names for x=0, x=1 and x=2.
	p.NominalX("Uniform\nDistribution", "Normal\nDistribution",
		"Exponential\nDistribution")
	return p
}

// makeLegend returns a legend with the default
// parameter settings.
func makeLegend() (Legend, error) {
	font, err := vg.MakeFont(DefaultFont, vg.Points(12))
	if err != nil {
		return Legend{}, err
	}
	return Legend{
		ThumbnailWidth: vg.Points(20),
		TextStyle:      draw.TextStyle{Font: font},
	}, nil
}

// Example_horizontalBoxPlots draws horizontal boxplots
// with some labels on their points.
func Example_horizontalBoxPlots() *plot.Plot {
	rand.Seed(int64(0))
	n := 100
	uniform := make(valueLabels, n)
	normal := make(valueLabels, n)
	expon := make(valueLabels, n)
	for i := 0; i < n; i++ {
		uniform[i].Value = rand.Float64()
		uniform[i].Label = fmt.Sprintf("%4.4f", uniform[i].Value)
		normal[i].Value = rand.NormFloat64()
		normal[i].Label = fmt.Sprintf("%4.4f", normal[i].Value)
		expon[i].Value = rand.ExpFloat64()
		expon[i].Label = fmt.Sprintf("%4.4f", expon[i].Value)
	}

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Horizontal Box Plot"
	p.X.Label.Text = "plotter.Values"

	// Make boxes for our data and add them to the plot.
	uniBox := must(plotter.MakeHorizBoxPlot(vg.Points(20), 0, uniform)).(plotter.HorizBoxPlot)
	uniLabels, err := uniBox.OutsideLabels(uniform)
	if err != nil {
		panic(err)
	}

	normBox := must(plotter.MakeHorizBoxPlot(vg.Points(20), 1, normal)).(plotter.HorizBoxPlot)
	normLabels, err := normBox.OutsideLabels(normal)
	if err != nil {
		panic(err)
	}

	expBox := must(plotter.MakeHorizBoxPlot(vg.Points(20), 2, expon)).(plotter.HorizBoxPlot)
	expLabels, err := expBox.OutsideLabels(expon)
	if err != nil {
		panic(err)
	}
	p.Add(uniBox, uniLabels, normBox, normLabels, expBox, expLabels)

	// Add a GlyphBox plotter for debugging.
	p.Add(plotter.NewGlyphBoxes())

	// Set the Y axis of the plot to nominal with
	// the given names for y=0, y=1 and y=2.
	p.NominalY("Uniform\nDistribution", "Normal\nDistribution",
		"Exponential\nDistribution")
	return p
}

func main() {
	var levels []float64
	for l := 100.5; l < volcano.Matrix.(*mat64.Dense).Max(); l += 5 {
		levels = append(levels, l)
	}
	c := plotter.NewContour(volcano, levels, palette.Rainbow(len(levels), (palette.Yellow+palette.Red)/2, palette.Blue, 1, 1, 1))
	quarterStyle := draw.LineStyle{
		Color:  color.Black,
		Width:  vg.Points(0.5),
		Dashes: []vg.Length{0.2, 0.4},
	}
	halfStyle := draw.LineStyle{
		Color:  color.Black,
		Width:  vg.Points(0.5),
		Dashes: []vg.Length{5, 2, 1, 2},
	}
	c.LineStyles = append(c.LineStyles, quarterStyle, halfStyle, quarterStyle)

	h := plotter.NewHeatMap(volcano, palette.Heat(len(levels)*2, 1))

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Maunga Whau Volcano"

	p.Add(h)
	p.Add(c)

	p.X.Padding = 0
	p.Y.Padding = 0
	_, p.X.Max, _, p.Y.Max = h.DataRange()

	name := "example_volcano"

	for _, ext := range []string{
		".eps",
		".pdf",
		".svg",
		".png",
		".tiff",
		".jpg",
	} {
		if err := p.Save(4, 4, name+ext); err != nil {
			panic(err)
		}
	}
}

func Example_groupedQuartPlots() *plot.Plot {
	rand.Seed(int64(0))
	n := 100
	uniform := make(plotter.Values, n)
	normal := make(plotter.Values, n)
	expon := make(plotter.Values, n)
	for i := 0; i < n; i++ {
		uniform[i] = rand.Float64()
		normal[i] = rand.NormFloat64()
		expon[i] = rand.ExpFloat64()
	}

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Box Plot"
	p.Y.Label.Text = "plotter.Values"

	w := vg.Points(10)
	for x := 0.0; x < 3.0; x++ {
		b0 := must(plotter.NewQuartPlot(x, uniform)).(*plotter.QuartPlot)
		b0.Offset = -w
		b1 := must(plotter.NewQuartPlot(x, normal)).(*plotter.QuartPlot)
		b2 := must(plotter.NewQuartPlot(x, expon)).(*plotter.QuartPlot)
		b2.Offset = w
		p.Add(b0, b1, b2)
	}
	p.Add(plotter.NewGlyphBoxes())

	p.NominalX("Group 0", "Group 1", "Group 2")
	return p
}

// An example of making a histogram.
func Example_histogram() *plot.Plot {
	rand.Seed(int64(0))
	n := 10000
	vals := make(plotter.Values, n)
	for i := 0; i < n; i++ {
		vals[i] = rand.NormFloat64()
	}

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Histogram"
	h, err := plotter.NewHist(vals, 16)
	if err != nil {
		panic(err)
	}
	h.Normalize(1)
	p.Add(h)

	// The normal distribution function
	norm := plotter.NewFunction(stdNorm)
	norm.Color = color.RGBA{R: 255, A: 255}
	norm.Width = vg.Points(2)
	p.Add(norm)

	return p
}

// DrawGlyph implements the Glyph interface.
func (RingGlyph) DrawGlyph(c *Canvas, sty GlyphStyle, pt Point) {
	c.SetLineStyle(LineStyle{Color: sty.Color, Width: vg.Points(0.5)})
	var p vg.Path
	p.Move(pt.X+sty.Radius, pt.Y)
	p.Arc(pt.X, pt.Y, sty.Radius, 0, 2*math.Pi)
	p.Close()
	c.Stroke(p)
}

// Example_points draws some scatter points, a line,
// and a line with points.
func Example_points() *plot.Plot {
	rand.Seed(int64(0))

	n := 15
	scatterData := randomPoints(n)
	lineData := randomPoints(n)
	linePointsData := randomPoints(n)

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Points Example"
	p.X.Label.Text = "X"
	p.Y.Label.Text = "Y"
	p.Add(plotter.NewGrid())

	s := must(plotter.NewScatter(scatterData)).(*plotter.Scatter)
	s.GlyphStyle.Color = color.RGBA{R: 255, B: 128, A: 255}
	s.GlyphStyle.Radius = vg.Points(3)

	l := must(plotter.NewLine(lineData)).(*plotter.Line)
	l.LineStyle.Width = vg.Points(1)
	l.LineStyle.Dashes = []vg.Length{vg.Points(5), vg.Points(5)}
	l.LineStyle.Color = color.RGBA{B: 255, A: 255}

	lpLine, lpPoints, err := plotter.NewLinePoints(linePointsData)
	if err != nil {
		panic(err)
	}
	lpLine.Color = color.RGBA{G: 255, A: 255}
	lpPoints.Shape = draw.CircleGlyph{}
	lpPoints.Color = color.RGBA{R: 255, A: 255}

	p.Add(s, l, lpLine, lpPoints)
	p.Legend.Add("scatter", s)
	p.Legend.Add("line", l)
	p.Legend.Add("line points", lpLine, lpPoints)

	return p
}

// Example_functions draws some functions.
func Example_functions() *plot.Plot {
	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Functions"
	p.X.Label.Text = "X"
	p.Y.Label.Text = "Y"

	quad := plotter.NewFunction(func(x float64) float64 { return x * x })
	quad.Color = color.RGBA{B: 255, A: 255}

	exp := plotter.NewFunction(func(x float64) float64 { return math.Pow(2, x) })
	exp.Dashes = []vg.Length{vg.Points(2), vg.Points(2)}
	exp.Width = vg.Points(2)
	exp.Color = color.RGBA{G: 255, A: 255}

	sin := plotter.NewFunction(func(x float64) float64 { return 10*math.Sin(x) + 50 })
	sin.Dashes = []vg.Length{vg.Points(4), vg.Points(5)}
	sin.Width = vg.Points(4)
	sin.Color = color.RGBA{R: 255, A: 255}

	p.Add(quad, exp, sin)
	p.Legend.Add("x^2", quad)
	p.Legend.Add("2^x", exp)
	p.Legend.Add("10*sin(x)+50", sin)
	p.Legend.ThumbnailWidth = 0.5 * vg.Inch

	p.X.Min = 0
	p.X.Max = 10
	p.Y.Min = 0
	p.Y.Max = 100
	return p
}

func Example_bubbles() *plot.Plot {
	rand.Seed(int64(0))
	n := 10
	bubbleData := randomTriples(n)

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Bubbles"
	p.X.Label.Text = "X"
	p.Y.Label.Text = "Y"

	bs, err := plotter.NewBubbles(bubbleData, vg.Points(1), vg.Points(20))
	if err != nil {
		panic(err)
	}
	bs.Color = color.RGBA{R: 196, B: 128, A: 255}
	p.Add(bs)

	return p
}

// AddStackedAreaPlots adds stacked area plot plotters to a plot.
// The variadic arguments must be either strings
// or plotter.Valuers.  Each valuer adds a stacked area
// plot to the plot below the stacked area plots added
// before it.  If a plotter.Valuer is immediately
// preceeded by a string then the string value is used to
// label the legend.
// Plots should be added in order of tallest to shortest,
// because they will be drawn in the order they are added
// (i.e. later plots will be painted over earlier plots).
//
// If an error occurs then none of the plotters are added
// to the plot, and the error is returned.
func AddStackedAreaPlots(plt *plot.Plot, xs plotter.Valuer, vs ...interface{}) error {
	var ps []plot.Plotter
	names := make(map[*plotter.Line]string)
	name := ""
	var i int

	for _, v := range vs {
		switch t := v.(type) {
		case string:
			name = t

		case plotter.Valuer:
			if xs.Len() != t.Len() {
				return errors.New("X/Y length mismatch")
			}

			// Make a line plotter and set its style.
			l, err := plotter.NewLine(combineXYs{xs: xs, ys: t})
			if err != nil {
				return err
			}

			l.LineStyle.Width = vg.Points(0)
			color := Color(i)
			i++
			l.ShadeColor = &color

			ps = append(ps, l)

			if name != "" {
				names[l] = name
				name = ""
			}

		default:
			panic(fmt.Sprintf("AddStackedAreaPlots handles strings and plotter.Valuers, got %T", t))
		}
	}

	plt.Add(ps...)
	for p, n := range names {
		plt.Legend.Add(n, p)
	}

	return nil
}