Python+matplotlib实现填充螺旋实例

import matplotlib.pyplot as pltimport numpy as nptheta = np.arange(0, 8*np.pi, 0.1)a = 1b = .2for dt in np.arange(0, 2*np.pi, np.pi/2.0):  x = a*np.cos(theta + dt)*np.exp(b*theta)  y = a*np.sin(theta + dt)*np.exp(b*theta)  dt = dt + np.pi/4.0  x2 = a*np.cos(theta + dt)*np.exp(b*theta)  y2 = a*np.sin(theta + dt)*np.exp(b*theta)  xf = np.concatenate((x, x2[::-1]))  yf = np.concatenate((y, y2[::-1]))  p1 = plt.fill(xf, yf)plt.show()