轴方法set_theta_zero_location
和set_theta_direction
允许您分别指定零位置和增加theta的方向。下面是Matplotlib示例的修改版本。
import numpy as np
import matplotlib.pyplot as plt
r = np.arange(0, 2, 0.01)
theta = 2 * np.pi * r
ax = plt.subplot(111, projection='polar')
ax.plot(theta, r)
ax.set_rmax(2)
ax.set_rticks([0.5, 1, 1.5, 2]) # less radial ticks
ax.set_rlabel_position(-22.5) # get radial labels away from plotted line
ax.grid(True)
# ---- mod here ---- #
ax.set_theta_zero_location("N") # theta=0 at the top
ax.set_theta_direction(-1) # theta increasing clockwise
# ---- mod here ---- #
ax.set_title("A line plot on a polar axis", va='bottom')
plt.show()
请注意,对于箭头图(quiverplot),这些方法目前会产生奇怪的结果(详见GitHub问题)。