Python中的 matplotlib.patches.Rectangle

Matplotlib是Python中用于数组二维图的惊人可视化库。 Matplotlib 是一个基于 NumPy 数组的多平台数据可视化库，旨在与更广泛的 SciPy 堆栈一起使用。

matplotlib.patches.Rectangle

matplotlib.patches.Rectangle类用于在左下方 xy = (x, y) 处以指定的宽度、高度和旋转角度将补丁矩形化。

Syntax: class matplotlib.patches.Rectangle(xy, width, height, angle=0.0, **kwargs)

Parameters:

• xy: Lower left point to start the rectangle plotting
• width : width of the rectangle
• height: Height of the rectangle.
• angle: Angle of rotation of the rectangle.

下表列出了有效的 kwargs；

PROPERTY	DESCRIPTION
agg_filter	a filter function that takes a (m, n, 3) float array and a dpi value that returns a (m, n, 3) array
alpha	float or None
animated	bool
antialiased or aa	unknown
capstyle	{‘butt’, ’round’, ‘projecting’}
clip_box	Bbox
clip_on	bool
clip_path	[(Path, Transform)|Patch|None]
color	color or sequence of rgba tuples
contains	callable
edgecolor or ec or edgecolors	color or None or ‘auto’
facecolor or fc or facecolors	color or None
figure	figure
fill	bool
gid	str
hatch	{‘/’, ‘\’, ‘|’, ‘-‘, ‘+’, ‘x’, ‘o’, ‘O’, ‘.’, ‘*’}
in_layout	bool
joinstyle	{‘miter’, ’round’, ‘bevel’}
linestyle or ls	{‘-‘, ‘–‘, ‘-.’, ‘:’, ”, (offset, on-off-seq), …}
linewidth or linewidths or lw	float or None
path_effects	AbstractPathEffect
picker	None or bool or float or callable
path_effects	AbstractPathEffect
picker	float or callable[[Artist, Event], Tuple[bool, dict]]
rasterized	bool or None
sketch_params	(scale: float, length: float, randomness: float)
snap	bool or None
transform	matplotlib.transforms.Transform
url	str
visible	bool
zorder	float

示例 1：

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.patches import Rectangle
  
  
# The image
X = np.arange(16).reshape(4, 4)
  
# highlight some feature in the
# middle boxes.
fig = plt.figure()
  
ax = fig.add_subplot(111)
ax.imshow(X, cmap = plt.cm.gray,
          interpolation ='nearest')
ax.add_patch( Rectangle((0.5, 0.5),
                        2, 2,
                        fc ='none', 
                        ec ='g',
                        lw = 10) )
  
plt.show()

输出：

示例 2：

import matplotlib
import matplotlib.pyplot as plt
  
  
fig = plt.figure()
ax = fig.add_subplot(111)
  
rect1 = matplotlib.patches.Rectangle((-200, -100),
                                     400, 200,
                                     color ='green')
  
rect2 = matplotlib.patches.Rectangle((0, 150),
                                     300, 20,
                                     color ='pink')
  
rect3 = matplotlib.patches.Rectangle((-300, -50),
                                     40, 200,
                                     color ='yellow')
  
ax.add_patch(rect1)
ax.add_patch(rect2)
ax.add_patch(rect3)
  
plt.xlim([-400, 400])
plt.ylim([-400, 400])
  
plt.show()

输出：