Matplotlib：在堆叠饼图中放大、填充和居中图例

Question

我有一个代码块，可以生成垂直对齐的饼图：

import matplotlib.pyplot as plt
import numpy

labels=['Ph 1', 'Ph 2','Ph 3']
colors = ['darkred', 'gold', 'green']
explode = (0.1, 0.1, 0.1)
event1=numpy.array([93.90,0.45,5.65])
event2=numpy.array([82.96,0.86,16.17])
event3=numpy.array([69.25,1.20,29.55])
fig1, (ax1,ax2,ax3)=plt.subplots(3,1,subplot_kw={'aspect':'equal'})
ax2.legend(labels, loc=(-0.05, 0.05), shadow=True)
ax1.pie(event1, explode=explode, colors=colors)
ax2.pie(event2, explode=explode, colors=colors)
ax3.pie(event3, explode=explode, colors=colors)
plt.show()

我希望图例与中心饼图对齐，但要放在其左侧。到目前为止，我得到了一个非常小的图例，它是空的，不可读的，并且在错误的位置。怎么解决？

Answer 1

如何使用补丁程序，如下所示：

import matplotlib.pyplot as plt
import matplotlib.patches as mpatches
import numpy

labels= ['Ph 1', 'Ph 2', 'Ph 3']
colors = ['darkred', 'gold', 'green']
explode = (0.1, 0.1, 0.1)
event1=numpy.array([93.90,0.45,5.65])
event2=numpy.array([82.96,0.86,16.17])
event3=numpy.array([69.25,1.20,29.55])
fig1, (ax1,ax2,ax3) = plt.subplots(3,1,subplot_kw={'aspect':'equal'})

ph1 = mpatches.Patch(color='darkred', label='Ph 1')
ph2 = mpatches.Patch(color='gold', label='Ph 2')
ph3 = mpatches.Patch(color='green', label='Ph 3')

ax2.legend(handles=[ph1, ph2, ph3], fontsize=15, loc=(-1.05, 0.15), shadow=True)

ax1.pie(event1, explode=explode, colors=colors)
ax2.pie(event2, explode=explode, colors=colors)
ax3.pie(event3, explode=explode, colors=colors)
plt.show()

这将显示如下：