text: """
  Demonstrate the mixing of 2d and 3d subplots
  """
  from mpl_toolkits.mplot3d import Axes3D
  import matplotlib.pyplot as plt
  import numpy as np
  
  def f(t):
      s1 = np.cos(2*np.pi*t)
      e1 = np.exp(-t)
      return np.multiply(s1,e1)
  
  
  ################
  # First subplot
  ################
  t1 = np.arange(0.0, 5.0, 0.1)
  t2 = np.arange(0.0, 5.0, 0.02)
  t3 = np.arange(0.0, 2.0, 0.01)
  
  # Twice as tall as it is wide.
  fig = plt.figure(figsize=plt.figaspect(2.))
  fig.suptitle('A tale of 2 subplots')
  ax = fig.add_subplot(2, 1, 1)
  l = ax.plot(t1, f(t1), 'bo',
              t2, f(t2), 'k--', markerfacecolor='green')
  ax.grid(True)
  ax.set_ylabel('Damped oscillation')
  
  
  #################
  # Second subplot
  #################
  ax = fig.add_subplot(2, 1, 2, projection='3d')
  X = np.arange(-5, 5, 0.25)
  xlen = len(X)
  Y = np.arange(-5, 5, 0.25)
  ylen = len(Y)
  X, Y = np.meshgrid(X, Y)
  R = np.sqrt(X**2 + Y**2)
  Z = np.sin(R)
  
  surf = ax.plot_surface(X, Y, Z, rstride=1, cstride=1,
          linewidth=0, antialiased=False)
  
  ax.set_zlim3d(-1, 1)
  
  plt.show()
  