title: get numpy array of matplotlib tricontourf
body: <p>I had x,y,height vars to build a contour in python.
  I created a Triangulation grid using </p>
  
  <p>x,y,height and traing are numpy arrays</p>
  
  <pre><code>tri = Tri.Triangulation(x, y, triang)
  </code></pre>
  
  <p>then i did a contour using tricontourf</p>
  
  <pre><code>tricontourf(tri,height)
  </code></pre>
  
  <p>how can i get the output of the tricontourf into a numpy array. I can display the image using pyplot but I dont want to.</p>
  
  <p>when I tried this:</p>
  
  <pre><code>triout = tricontourf(tri,height)
  print triout
  </code></pre>
  
  <p>I got:</p>
  
  <pre><code>&lt;matplotlib.tri.tricontour.TriContourSet instance at 0xa9ab66c&gt;
  </code></pre>
  
  <p>I need to get the image data and if I could get numpy array its easy for me.</p>
  
  <p>Is it possible to do this?</p>
  
  <p>if its not possible can I do what tricontourf does without matplotlib in python?</p>