title: Representing 4D data in mplot 3D using colormaps
body: <p>Is there a way to change the value that the colormap is tied to in an mplot3d surface plot?<br>
  As an example, I'm trying to represent surface temperature for an object:</p>
  
  <pre><code>import matplotlib.pyplot as plt
  import numpy as np
  
  fig = plt.figure()
  ax = fig.add_subplot(111, projection='3d')
  
  z = np.array([0,1,2,3,4,5,6,7,8,9,10])
  radius = np.array([0,1,1.5,1,0,2,4,5,4,2,1])
  temp = np.array([150,200,210,220,225,220,195,185,160,150,140])
  
  angle = np.linspace(0,2*np.pi,20)
  Z,ANG = np.meshgrid(z,angle)
  # transform them to cartesian system
  X,Y = radius*np.cos(ANG),radius*np.sin(ANG)
  
  ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap='jet')
  plt.show()
  </code></pre>
  
  <p>This generates a 3d representation of the object, but the colormap is by default tied to the z-axis value.  Can the colormap be tied to the 'temp' value?</p>
  
  <p>(in this example, 'temp' maps on to Z the same way that the 'radius' values do)</p>
  
  <p>I'm aware of tools like MayaVI, but if it's possible I'm hoping for a solution within matplotlib.</p>