Code
import numpy as np
import matplotlib.pyplot as plt
= np.arange(0, 2, 0.01)
r = 4 * np.pi * r
theta = plt.subplots(
fig, ax = {'projection': 'polar'}
subplot_kw
)
ax.plot(theta, r)0.5, 1, 1.5, 2])
ax.set_rticks([True)
ax.grid( plt.show()