1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
// Copyright ©2019 The Gonum Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package plotter_test
import (
"testing"
"gonum.org/v1/plot"
// "gonum.org/v1/plot/cmpimg"
"gonum.org/v1/plot/plotter"
"gonum.org/v1/plot/vg/draw"
"gonum.org/v1/plot/vg/vgimg"
)
type field struct {
c, r int
fn func(x, y float64) plotter.XY
}
func (f field) Dims() (c, r int) { return f.c, f.r }
func (f field) Vector(c, r int) plotter.XY { return f.fn(f.X(c), f.Y(r)) }
func (f field) X(c int) float64 {
if c < 0 || c >= f.c {
panic("column index out of range")
}
return float64(c - f.c/2)
}
func (f field) Y(r int) float64 {
if r < 0 || r >= f.r {
panic("row index out of range")
}
return float64(r - f.r/2)
}
/*
func TestField(t *testing.T) {
cmpimg.CheckPlot(ExampleField, t, "field.png")
}
func TestFieldColors(t *testing.T) {
cmpimg.CheckPlot(ExampleField_colors, t, "color_field.png")
}
func TestFieldGophers(t *testing.T) {
cmpimg.CheckPlot(ExampleField_gophers, t, "gopher_field.png")
}
*/
func TestFieldDims(t *testing.T) {
for _, test := range []struct {
rows int
cols int
}{
{rows: 1, cols: 2},
{rows: 2, cols: 1},
{rows: 2, cols: 2},
} {
func() {
defer func() {
r := recover()
if r != nil {
t.Errorf("unexpected panic for rows=%d cols=%d: %v", test.rows, test.cols, r)
}
}()
f := plotter.NewField(field{
r: test.rows, c: test.cols,
fn: func(x, y float64) plotter.XY {
return plotter.XY{
X: y,
Y: -x,
}
},
})
p, err := plot.New()
if err != nil {
t.Errorf("unexpected error: %v", err)
}
p.Add(f)
img := vgimg.New(250, 175)
dc := draw.New(img)
p.Draw(dc)
}()
}
}
|
