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import matplotlib.pyplot as plt
import numpy as np
theta = np.arange(0, 8*np.pi, 0.1)
a = 1
b = .2
for 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()
Keywords: python, matplotlib, pylab, example, codex (see Search examples)