以最简单的方式将图例添加到Matplotlib中的PyPlot

label=

plot()

legend(loc='upperleft')

考虑以下示例（使用Python 3.8.0测试）：

import numpy as npimport matplotlib.pyplot as pltx = np.linspace(0, 20, 1000)y1 = np.sin(x)y2 = np.cos(x)plt.plot(x, y1, "-b", label="sine")plt.plot(x, y2, "-r", label="cosine")plt.legend(loc="upper left")plt.ylim(-1.5, 2.0)plt.show()

从本教程中略作修改：http
:
//jakevdp.github.io/mpl_tutorial/tutorial_pages/tut1.html