艺术家中的艺术家
重写基本方法,以便一个艺术家对象可以包含另一个艺术家对象。在这种情况下,该行包含一个文本实例来为其添加标签。
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.lines as lines
import matplotlib.transforms as mtransforms
import matplotlib.text as mtext
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, '')
lines.Line2D.__init__(self, *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)
lines.Line2D.set_figure(self, figure)
def set_axes(self, axes):
self.text.set_axes(axes)
lines.Line2D.set_axes(self, axes)
def set_transform(self, transform):
# 2 pixel offset
texttrans = transform + mtransforms.Affine2D().translate(2, 2)
self.text.set_transform(texttrans)
lines.Line2D.set_transform(self, transform)
def set_data(self, x, y):
if len(x):
self.text.set_position((x[-1], y[-1]))
lines.Line2D.set_data(self, x, y)
def draw(self, renderer):
# draw my label at the end of the line with 2 pixel offset
lines.Line2D.draw(self, 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_text('line label')
line.text.set_color('red')
line.text.set_fontsize(16)
ax.add_line(line)
plt.show()
参考
此示例显示了以下函数、方法、类和模块的使用:
import matplotlib
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