饼图
import matplotlib.pyplot as plt
plt.style.use('seaborn')
X = [15, 30, 45, 10]
labels = 'I', 'II', 'III', 'IV'
ax = plt.subplot()
ax.pie(X, labels=labels, autopct='%1.1f%%', startangle=90)
plt.show()

正圆
import matplotlib.pyplot as plt
plt.style.use('seaborn')
X = [15, 30, 45, 10]
labels = 'I', 'II', 'III', 'IV'
ax = plt.subplot()
ax.pie(X, labels=labels, autopct='%1.1f%%', startangle=90)
# 设置 x 轴与 y 轴相等
ax.axis('equal')
plt.show()

强调
import matplotlib.pyplot as plt
plt.style.use('seaborn')
X = [15, 30, 45, 10]
labels = 'I', 'II', 'III', 'IV'
explode = [0, 0.1, 0, 0]
ax = plt.subplot()
# explode 参数可以强调数据
ax.pie(X, explode=explode, labels=labels, autopct='%1.1f%%', startangle=90)
ax.axis('equal')
plt.show()
