python双Y轴

import matplotlib.pyplot as plt import numpy as np x = np.arange(0., np.e, 0.01) y1 = np.exp(-x) y2 = np.log(x) fig = plt.figure() sns.set_style('white') ax1 = fig.add_subplot(111) ax1.plot(x, y1) ax1.set_ylabel('Y values for exp(-x)') ax1.set_title("Double Y axis") ax2 = ax1.twinx() # this is the important function ax2.plot(x, y2, 'r') ax2.set_xlim([0, np.e]) ax2.set_ylabel('Y values for ln(x)') ax2.set_xlabel('Same X for both exp(-x) and ln(x)') plt.show() fig.savefig('doubleY.pdf') 

# 生成画布, 并设定标题 plt.figure(figsize=(8, 6), dpi=80) plt.grid(True) # 画图的另外一种方式 ax_1 = plt.subplot(111) ax_1.plot(x, y_cos, color="blue", linewidth=2.0, linestyle="--", label="cos") ax_1.legend(loc="upper left", shadow=True) # 设置Y轴(左边) ax_1.set_ylabel("cosy") ax_1.set_ylim(-1.0, 1.0) ax_1.set_yticks(np.linspace(-1, 1, 9, endpoint=True)) # 画图的另外一种方式 ax_2 = ax_1.twinx() ax_2.plot(x, y_sin, color="green", linewidth=2.0, linestyle="-", label="sin") ax_2.legend(loc="upper right", shadow=True) # 设置Y轴(右边) ax_2.set_ylabel("siny") ax_2.set_ylim(-2.0, 2.0) ax_2.set_yticks(np.linspace(-2, 2, 9, endpoint=True)) # 设置X轴(共同) ax_1.set_xlabel("x") ax_1.set_xlim(-4.0, 4.0) ax_1.set_xticks(np.linspace(-4, 4, 9, endpoint=True)) # 图形显示 plt.show()