text: """
  =================
  An animated image
  =================
  
  This example demonstrates how to animate an image.
  """
  import numpy as np
  import matplotlib.pyplot as plt
  import matplotlib.animation as animation
  
  fig = plt.figure()
  
  
  def f(x, y):
      return np.sin(x) + np.cos(y)
  
  x = np.linspace(0, 2 * np.pi, 120)
  y = np.linspace(0, 2 * np.pi, 100).reshape(-1, 1)
  
  im = plt.imshow(f(x, y), animated=True)
  
  
  def updatefig(*args):
      global x, y
      x += np.pi / 15.
      y += np.pi / 20.
      im.set_array(f(x, y))
      return im,
  
  ani = animation.FuncAnimation(fig, updatefig, interval=50, blit=True)
  plt.show()