// 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
}
// 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
}
// AddScatters adds Scatter plotters to a plot.
// The variadic arguments must be either strings
// or plotter.XYers. Each plotter.XYer is added to
// the plot using the next color, and glyph shape
// via the Color and Shape functions. If a
// plotter.XYer is immediately preceeded by
// a string then a legend entry is added to the plot
// using the string as the name.
//
// If an error occurs then none of the plotters are added
// to the plot, and the error is returned.
func AddScatters(plt *plot.Plot, vs ...interface{}) error {
var ps []plot.Plotter
names := make(map[*plotter.Scatter]string)
name := ""
var i int
for _, v := range vs {
switch t := v.(type) {
case string:
name = t
case plotter.XYer:
s, err := plotter.NewScatter(t)
if err != nil {
return err
}
s.Color = Color(i)
s.Shape = Shape(i)
i++
ps = append(ps, s)
if name != "" {
names[s] = name
name = ""
}
default:
panic(fmt.Sprintf("AddScatters handles strings and plotter.XYers, got %T", t))
}
}
plt.Add(ps...)
for p, n := range names {
plt.Legend.Add(n, p)
}
return nil
}
func TestIssue179(t *testing.T) {
scatter, err := plotter.NewScatter(plotter.XYs{{1, 1}, {0, 1}, {0, 0}})
if err != nil {
log.Fatal(err)
}
p, err := plot.New()
if err != nil {
log.Fatal(err)
}
p.Add(scatter)
p.HideAxes()
c := vgimg.JpegCanvas{Canvas: vgimg.New(5.08*vg.Centimeter, 5.08*vg.Centimeter)}
p.Draw(draw.New(c))
b := bytes.NewBuffer([]byte{})
if _, err = c.WriteTo(b); err != nil {
t.Error(err)
}
f, err := os.Open(filepath.Join("testdata", "issue179.jpg"))
if err != nil {
t.Error(err)
}
defer f.Close()
want, err := ioutil.ReadAll(f)
if err != nil {
t.Error(err)
}
if !bytes.Equal(b.Bytes(), want) {
t.Error("Image mismatch")
}
}
func TestIssue179(t *testing.T) {
if !hasX11() {
t.Skip("no X11 environment")
}
scatter, err := plotter.NewScatter(plotter.XYs{{1, 1}, {0, 1}, {0, 0}})
if err != nil {
t.Fatalf("error: %v\n", err)
}
p, err := plot.New()
if err != nil {
t.Fatalf("error: %v\n", err)
}
p.Add(scatter)
p.HideAxes()
c, err := New(5.08*vg.Centimeter, 5.08*vg.Centimeter, "test issue179")
if err != nil {
t.Fatalf("error: %v\n", err)
}
p.Draw(draw.New(c))
b := bytes.NewBuffer([]byte{})
err = jpeg.Encode(b, c.ximg, nil)
if err != nil {
t.Error(err)
}
f, err := os.Open(filepath.Join("..", "vgimg", "testdata", "issue179.jpg"))
if err != nil {
t.Error(err)
}
defer f.Close()
want, err := ioutil.ReadAll(f)
if err != nil {
t.Error(err)
}
if !bytes.Equal(b.Bytes(), want) {
t.Error("Image mismatch")
}
}
// 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
}
func TestPersistency(t *testing.T) {
// Get some random points
rand.Seed(0)
n := 15
scatterData := randomPoints(n)
lineData := randomPoints(n)
linePointsData := randomPoints(n)
p, err := plot.New()
if err != nil {
t.Fatalf("error creating plot: %v\n", err)
}
p.Title.Text = "Plot Example"
p.X.Label.Text = "X"
p.Y.Label.Text = "Y"
// Use a custom tick marker function that computes the default
// tick marks and re-labels the major ticks with commas.
p.Y.Tick.Marker = commaTicks{}
// Draw a grid behind the data
p.Add(plotter.NewGrid())
// Make a scatter plotter and set its style.
s, err := plotter.NewScatter(scatterData)
if err != nil {
panic(err)
}
s.GlyphStyle.Color = color.RGBA{R: 255, B: 128, A: 255}
// Make a line plotter and set its style.
l, err := plotter.NewLine(lineData)
if err != nil {
panic(err)
}
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}
// Make a line plotter with points and set its style.
lpLine, lpPoints, err := plotter.NewLinePoints(linePointsData)
if err != nil {
panic(err)
}
lpLine.Color = color.RGBA{G: 255, A: 255}
lpPoints.Shape = draw.PyramidGlyph{}
lpPoints.Color = color.RGBA{R: 255, A: 255}
// Add the plotters to the plot, with a legend
// entry for each
p.Add(s, l, lpLine, lpPoints)
p.Legend.Add("scatter", s)
p.Legend.Add("line", l)
p.Legend.Add("line points", lpLine, lpPoints)
// Save the plot to a PNG file.
err = p.Save(4, 4, "test-persistency.png")
if err != nil {
t.Fatalf("error saving to PNG: %v\n", err)
}
defer os.Remove("test-persistency.png")
buf := new(bytes.Buffer)
enc := gob.NewEncoder(buf)
err = enc.Encode(p)
if err != nil {
t.Fatalf("error gob-encoding plot: %v\n", err)
}
// TODO(sbinet): impl. BinaryMarshal for plot.Plot and vg.Font
// {
// dec := gob.NewDecoder(buf)
// var p plot.Plot
// err = dec.Decode(&p)
// if err != nil {
// t.Fatalf("error gob-decoding plot: %v\n", err)
// }
// // Save the plot to a PNG file.
// err = p.Save(4, 4, "test-persistency-readback.png")
// if err != nil {
// t.Fatalf("error saving to PNG: %v\n", err)
// }
// defer os.Remove("test-persistency-readback.png")
// }
}