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
89
|
"""
=======================
Artist within an artist
=======================
Override basic methods so an artist can contain another
artist. In this case, the line contains a Text instance to label it.
"""
import matplotlib.pyplot as plt
import numpy as np
import matplotlib.lines as lines
import matplotlib.text as mtext
import matplotlib.transforms as mtransforms
class MyLine(lines.Line2D):
def __init__(self, *args, **kwargs):
# we'll update the position when the line data is set
self.text = mtext.Text(0, 0, '')
super().__init__(*args, **kwargs)
# we can't access the label attr until *after* the line is
# initiated
self.text.set_text(self.get_label())
def set_figure(self, figure):
self.text.set_figure(figure)
super().set_figure(figure)
# Override the Axes property setter to set Axes on our children as well.
@lines.Line2D.axes.setter
def axes(self, new_axes):
self.text.axes = new_axes
lines.Line2D.axes.fset(self, new_axes) # Call the superclass property setter.
def set_transform(self, transform):
# 2 pixel offset
texttrans = transform + mtransforms.Affine2D().translate(2, 2)
self.text.set_transform(texttrans)
super().set_transform(transform)
def set_data(self, x, y):
if len(x):
self.text.set_position((x[-1], y[-1]))
super().set_data(x, y)
def draw(self, renderer):
# draw my label at the end of the line with 2 pixel offset
super().draw(renderer)
self.text.draw(renderer)
# Fixing random state for reproducibility
np.random.seed(19680801)
fig, ax = plt.subplots()
x, y = np.random.rand(2, 20)
line = MyLine(x, y, mfc='red', ms=12, label='line label')
line.text.set_color('red')
line.text.set_fontsize(16)
ax.add_line(line)
plt.show()
# %%
#
# .. admonition:: References
#
# The use of the following functions, methods, classes and modules is shown
# in this example:
#
# - `matplotlib.lines`
# - `matplotlib.lines.Line2D`
# - `matplotlib.lines.Line2D.set_data`
# - `matplotlib.artist`
# - `matplotlib.artist.Artist`
# - `matplotlib.artist.Artist.draw`
# - `matplotlib.artist.Artist.set_transform`
# - `matplotlib.text`
# - `matplotlib.text.Text`
# - `matplotlib.text.Text.set_color`
# - `matplotlib.text.Text.set_fontsize`
# - `matplotlib.text.Text.set_position`
# - `matplotlib.axes.Axes.add_line`
# - `matplotlib.transforms`
# - `matplotlib.transforms.Affine2D`
|
