plot-function-svg
Plot 3D math equation z=f(x, y) with SVG format.
Some codes are referred from https://github.com/adonovan/gopl.io
licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
APIs
type PlotConfig struct {
Width int
Height int
Cells int
XYrange float64
Xoffset float64
Yoffset float64
Zscale float64
CameraAngle float64
Color bool
RightHand bool
}
func DefaultPlotConfig() *PlotConfig {
return &PlotConfig{
Width: 600,
Height: 320,
Cells: 100,
XYrange: 30.0,
Xoffset: 0,
Yoffset: 0,
Zscale: 0.4,
CameraAngle: math.Pi / 6,
Color: true,
RightHand: true,
}
}
// Draw an SVG to io.Writer. Default w (use nil) is os.Stdout. Default cfg (use nil) is DefaultPlotConfig().
func PlotSVG(f func(x, y float64) float64, w io.Writer, cfg *PlotConfig)
Right-hand coordinates (default):
z
|__ y
x /
Left-hand coordinates:
z
|__ x
y /
Examples
Example1:
f := func(x, y float64) float64 {
r := math.Hypot(x, y)
return math.Sin(r) / r
}
file, _ := os.Create("example1.svg")
plot.PlotSVG(f, file, nil)
Example2:
cfg := &plot.PlotConfig{
Width: 600,
Height: 400,
Cells: 100,
XYrange: 2,
Xoffset: 0.4,
Yoffset: 0.3,
Zscale: 0.1,
CameraAngle: math.Pi / 6,
Color: true,
RightHand: false,
}
f := func(x, y float64) float64 {
return 2*math.Pow(x, 2) + 0.5*math.Sin(-7*y)
}
file, _ := os.Create("example2.svg")
plot.PlotSVG(f, file, cfg)
