Exemple #1
0
// 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 = vg.Inches(0.5)

	p.X.Min = 0
	p.X.Max = 10
	p.Y.Min = 0
	p.Y.Max = 100
	return p
}
Exemple #2
0
func histPlot() *plot.Plot {
	// Draw some random values from the standard
	// normal distribution.
	rand.Seed(int64(0))
	v := make(plotter.Values, 1000)
	for i := range v {
		v[i] = rand.NormFloat64()
	}

	// Make a plot and set its title.
	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "Histogram"

	// Create a histogram of our values drawn
	// from the standard normal.
	h, err := plotter.NewHist(v, 16)
	if err != nil {
		panic(err)
	}
	// Normalize the area under the histogram to
	// sum to one.
	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
}
Exemple #3
0
// 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
}