// 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 }
// Example_quartPlots draws vertical quartile plots. func Example_quartPlots() *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 = "Quartile Plot" p.Y.Label.Text = "plotter.Values" p.Add(must(plotter.NewQuartPlot(0, uniform)).(*plotter.QuartPlot), must(plotter.NewQuartPlot(1, normal)).(*plotter.QuartPlot), must(plotter.NewQuartPlot(2, expon)).(*plotter.QuartPlot)) // 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 }
// 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 }
// 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 }
// 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 }
// 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 }
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 TestComplexContours(t *testing.T) { if !*visualDebug { return } for _, n := range []float64{0, 1, 2, 4, 8, 16, 32} { rand.Seed(0) data := make([]float64, 6400) for i := range data { r := float64(i/80) - 40 c := float64(i%80) - 40 data[i] = rand.NormFloat64()*n + math.Hypot(r, c) } m := unitGrid{mat64.NewDense(80, 80, data)} levels := []float64{-1, 3, 7, 9, 13, 15, 19, 23, 27, 31} c := NewContour(m, levels, palette.Rainbow(10, palette.Blue, palette.Red, 1, 1, 1)) plt, _ := plot.New() plt.Add(c) plt.X.Padding = 0 plt.Y.Padding = 0 plt.X.Max = 79.5 plt.Y.Max = 79.5 plt.Save(7, 7, fmt.Sprintf("complex_contour-%v.svg", n)) } }
func TestHeatMapWithContour(t *testing.T) { if !*visualDebug { return } m := unitGrid{mat64.NewDense(3, 4, []float64{ 2, 1, 4, 3, 6, 7, 2, 5, 9, 10, 11, 12, })} h := NewHeatMap(m, palette.Heat(12, 1)) levels := []float64{1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5, 10.5, 11.5} c := NewContour(m, levels, palette.Rainbow(10, palette.Blue, palette.Red, 1, 1, 1)) c.LineStyles[0].Width *= 5 plt, _ := plot.New() plt.Add(h) plt.Add(c) plt.Add(NewGlyphBoxes()) plt.X.Padding = 0 plt.Y.Padding = 0 plt.X.Max = 3.5 plt.Y.Max = 2.5 plt.Save(7, 7, "heat.svg") }
func Example_groupedHorizontalQuartPlots() *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.MakeHorizQuartPlot(x, uniform)).(plotter.HorizQuartPlot) b0.Offset = -w b1 := must(plotter.MakeHorizQuartPlot(x, normal)).(plotter.HorizQuartPlot) b2 := must(plotter.MakeHorizQuartPlot(x, expon)).(plotter.HorizQuartPlot) b2.Offset = w p.Add(b0, b1, b2) } p.Add(plotter.NewGlyphBoxes()) p.NominalY("Group 0", "Group 1", "Group 2") return p }
// Example_horizontalQuartPlots draws horizontal quartile plots // with some labels on their points. func Example_horizontalQuartPlots() *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 Quartile Plot" p.X.Label.Text = "plotter.Values" // Make boxes for our data and add them to the plot. uniBox := must(plotter.MakeHorizQuartPlot(0, uniform)).(plotter.HorizQuartPlot) uniLabels, err := uniBox.OutsideLabels(uniform) if err != nil { panic(err) } normBox := must(plotter.MakeHorizQuartPlot(1, normal)).(plotter.HorizQuartPlot) normLabels, err := normBox.OutsideLabels(normal) if err != nil { panic(err) } expBox := must(plotter.MakeHorizQuartPlot(2, expon)).(plotter.HorizQuartPlot) 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 }
// Example_verticalBoxPlots draws vertical boxplots // with some labels on their points. func Example_verticalBoxPlots() *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 = "Box Plot" p.Y.Label.Text = "plotter.Values" // Make boxes for our data and add them to the plot. uniBox := must(plotter.NewBoxPlot(vg.Points(20), 0, uniform)).(*plotter.BoxPlot) uniLabels, err := uniBox.OutsideLabels(uniform) if err != nil { panic(err) } normBox := must(plotter.NewBoxPlot(vg.Points(20), 1, normal)).(*plotter.BoxPlot) normLabels, err := normBox.OutsideLabels(normal) if err != nil { panic(err) } expBox := must(plotter.NewBoxPlot(vg.Points(20), 2, expon)).(*plotter.BoxPlot) expLabels, err := expBox.OutsideLabels(expon) if err != nil { panic(err) } p.Add(uniBox, uniLabels, normBox, normLabels, expBox, expLabels) // 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 }
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 lines(w vg.Length) (*plot.Plot, error) { p, err := plot.New() if err != nil { return nil, err } pts := plotter.XYs{{0, 0}, {0, 1}, {1, 0}, {1, 1}} line, err := plotter.NewLine(pts) line.Width = w if err != nil { return nil, err } p.Add(line) return p, nil }
func main() { rand.Seed(int64(0)) p, err := plot.New() if err != nil { panic(err) } p.Title.Text = "Plotutil example" p.X.Label.Text = "X" p.Y.Label.Text = "Y" err = plotutil.AddLinePoints( p, "First", randomPoints(15), ) if err != nil { panic(err) } cnvs, err := vgx11.New(4*96, 4*96, "Example") if err != nil { panic(err) } p.Draw(draw.New(cnvs)) cnvs.Paint() time.Sleep(5 * time.Second) err = plotutil.AddLinePoints( p, "Second", randomPoints(15), "Third", randomPoints(15), ) if err != nil { panic(err) } p.Draw(draw.New(cnvs)) cnvs.Paint() time.Sleep(10 * time.Second) // Save the plot to a PNG file. // if err := p.Save(4, 4, "points.png"); err != nil { // panic(err) // } }
// An example of making a stacked area chart. func Example_stackedAreaChart() *plot.Plot { p, err := plot.New() if err != nil { panic(err) } p.Title.Text = "Example: Software Version Comparison" p.X.Label.Text = "Date" p.Y.Label.Text = "Users (in thousands)" p.Legend.Top = true p.Legend.Left = true vals := []plotter.Values{ plotter.Values{0.02, 0.015, 0, 0, 0, 0, 0}, plotter.Values{0, 0.48, 0.36, 0.34, 0.32, 0.32, 0.28}, plotter.Values{0, 0, 0.87, 1.4, 0.64, 0.32, 0.28}, plotter.Values{0, 0, 0, 1.26, 0.34, 0.12, 0.09}, plotter.Values{0, 0, 0, 0, 2.48, 2.68, 2.13}, plotter.Values{0, 0, 0, 0, 0, 1.32, 0.54}, plotter.Values{0, 0, 0, 0, 0, 0.68, 5.67}, } err = plotutil.AddStackedAreaPlots(p, plotter.Values{2007, 2008, 2009, 2010, 2011, 2012, 2013}, "Version 3.0", stackValues{vs: vals[0:7]}, "Version 2.1", stackValues{vs: vals[0:6]}, "Version 2.0.1", stackValues{vs: vals[0:5]}, "Version 2.0", stackValues{vs: vals[0:4]}, "Version 1.1", stackValues{vs: vals[0:3]}, "Version 1.0", stackValues{vs: vals[0:2]}, "Beta", stackValues{vs: vals[0:1]}, ) if err != nil { panic(err) } return p }
// An example of making a bar chart. func Example_barChart() *plot.Plot { groupA := plotter.Values{20, 35, 30, 35, 27} groupB := plotter.Values{25, 32, 34, 20, 25} groupC := plotter.Values{12, 28, 15, 21, 8} groupD := plotter.Values{30, 42, 6, 9, 12} p, err := plot.New() if err != nil { panic(err) } p.Title.Text = "Bar chart" p.Y.Label.Text = "Heights" w := vg.Points(8) barsA := must(plotter.NewBarChart(groupA, w)).(*plotter.BarChart) barsA.Color = color.RGBA{R: 255, A: 255} barsA.Offset = -w / 2 barsB := must(plotter.NewBarChart(groupB, w)).(*plotter.BarChart) barsB.Color = color.RGBA{R: 196, G: 196, A: 255} barsB.Offset = w / 2 barsC := must(plotter.NewBarChart(groupC, w)).(*plotter.BarChart) barsC.Color = color.RGBA{B: 255, A: 255} barsC.XMin = 6 barsC.Offset = -w / 2 barsD := must(plotter.NewBarChart(groupD, w)).(*plotter.BarChart) barsD.Color = color.RGBA{B: 255, R: 255, A: 255} barsD.XMin = 6 barsD.Offset = w / 2 p.Add(barsA, barsB, barsC, barsD) p.Legend.Add("A", barsA) p.Legend.Add("B", barsB) p.Legend.Add("C", barsC) p.Legend.Add("D", barsD) p.Legend.Top = true p.NominalX("Zero", "One", "Two", "Three", "Four", "", "Six", "Seven", "Eight", "Nine", "Ten") return p }
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") } }
func ExampleErrorPoints() { // Get some random data. n, m := 5, 10 pts := make([]plotter.XYer, n) for i := range pts { xys := make(plotter.XYs, m) pts[i] = xys center := float64(i) for j := range xys { xys[j].X = center + (rand.Float64() - 0.5) xys[j].Y = center + (rand.Float64() - 0.5) } } plt, err := plot.New() if err != nil { panic(err) } mean95, err := NewErrorPoints(MeanAndConf95, pts...) if err != nil { panic(err) } medMinMax, err := NewErrorPoints(MedianAndMinMax, pts...) if err != nil { panic(err) } err = AddLinePoints(plt, "mean and 95% confidence", mean95, "median and minimum and maximum", medMinMax) if err != nil { panic(err) } if err := AddErrorBars(plt, mean95, medMinMax); err != nil { panic(err) } if err := AddScatters(plt, pts[0], pts[1], pts[2], pts[3], pts[4]); err != nil { panic(err) } plt.Save(4, 4, "centroids.png") }
// 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 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 }
func Example_heatMap() *plot.Plot { m := unitGrid{mat64.NewDense(3, 4, []float64{ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, })} h := plotter.NewHeatMap(m, palette.Heat(12, 1)) p, err := plot.New() if err != nil { panic(err) } p.Title.Text = "Heat map" p.Add(h) p.X.Padding = 0 p.Y.Padding = 0 p.X.Max = 3.5 p.Y.Max = 2.5 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") // } }