text: import numpy as np
  import matplotlib.pyplot as plt
  
  
  def f(t):
      return np.exp(-t) * np.cos(2 * np.pi * t)
  
  
  t1 = np.arange(0.0, 5.0, 0.1)
  t2 = np.arange(0.0, 5.0, 0.02)
  
  plt.figure(1)
  plt.subplot(211)
  plt.plot(t1, f(t1), 'bo', t2, f(t2), 'k')
  
  plt.subplot(212)
  plt.plot(t2, np.cos(2 * np.pi * t2), 'r--')
  plt.show()
  