matplotlib fill和fill_between

 import numpy as np
 import matplotlib.pyplot as plt

 x = np.linspace(0, 5 * np.pi, 1000)

 y1 = np.sin(x)
 y2 = np.sin(2 * x)

 plt.plot(x, y1, label = "$ y = sin(x) $")
 plt.plot(x, y2, label = "$ y = sin(2 * x) $")
 plt.legend(loc = 3)

 plt.show()

对函数与坐标轴之间的区域进行填充，使用fill函数

 import numpy as np
 import matplotlib.pyplot as plt

 x = np.linspace(0, 5 * np.pi, 1000)

 y1 = np.sin(x)
 y2 = np.sin(2 * x)

 plt.fill(x, y1, color = "g", alpha = 0.3)
 plt.fill(x, y2, color = "b", alpha = 0.3)

 plt.show()

填充两个函数之间的区域用fill_between

 import numpy as np
 import matplotlib.pyplot as plt

 x = np.linspace(0, 5 * np.pi, 1000)

 y1 = np.sin(x)
 y2 = np.sin(2 * x)

 plt.plot(x, y1, c = "g")
 plt.plot(x, y2, c = 'r')

 # fill_between 填充两个函数之间的区域
 # 两个函数之间的区域用黄色填充
 plt.fill_between(x, y1, y2, facecolor = "yellow")

 plt.show()