玩转坐标系：极坐标与直角坐标详解

3、

import numpy as np

import matplotlib.pyplot as plt

plt.rcParams['font.sans-serif'] = ['KaiTi']

theta = np.arange(0, 2*np.pi, np.pi/4)  # 角度

radii = np.arange(1,9,1)  # 极径

ax1 = plt.subplot(121,projection='polar')

ax1.plot(theta,radii,'--', color='m',lw=2)

plt.title("极坐标图")

ax2 = plt.subplot(122)

ax2.plot(theta,radii,'*', color='g',lw=2)

plt.title("直角坐标图")

plt.show()

4、极坐标的方向和0°位置

import matplotlib.pyplot as plt

import numpy as np

plt.rcParams['font.sans-serif'] = ['KaiTi']

theta=np.arange(0,np.pi,0.04)

ax1= plt.subplot(121, projection='polar')

ax2= plt.subplot(122, projection='polar')

ax1.set_theta_direction(-1)

# set_theta_direction设置极坐标的方向

ax1.set_title("极坐标的方向")

ax2.set_theta_zero_location('W')

# set_theta_zero_location设置极坐标0°位置

plt.title("极坐标0°位置")

ax1.plot(theta,theta/3,'*',lw=2)

ax2.plot(theta,theta/6,'--',lw=2)

plt.show()