title: Matplotlib plot pulse propagation in 3d
body: <p>I'd like to plot pulse propagation in such a way at each step, it plots the pulse shape. In other words, I want a serie of x-z plots, for each values of y. Something like this (without color):
  <img src="https://i.stack.imgur.com/q71Ja.jpg" alt="Pulse propagation"> </p>
  
  <p>How can I do this using matplotlib (or Mayavi)? Here is what I did so far:</p>
  
  <pre><code>def drawPropagation(beta2, C, z):
      """ beta2 in ps / km
          C is chirp
          z is an array of z positions """
      T = numpy.linspace(-10, 10, 100)
      sx = T.size
      sy = z.size
  
      T = numpy.tile(T, (sy, 1))
      z = numpy.tile(z, (sx, 1)).T
  
      U = 1 / numpy.sqrt(1 - 1j*beta2*z * (1 + 1j * C)) * numpy.exp(- 0.5 * (1 + 1j * C) * T * T / (1 - 1j*beta2*z*(1 + 1j*C)))
  
      fig = pyplot.figure()
      ax = fig.add_subplot(1,1,1, projection='3d')
      surf = ax.plot_wireframe(T, z, abs(U))
  </code></pre>