title: How do I include a matplotlib Figure object as subplot?
body: <p>How can I use a matplotlib Figure object as a subplot?  Specifically, I have a function that creates a matplotlib Figure object, and I would like to include this as a subplot in another Figure.</p>
  
  <p>In short, here's stripped-down pseudocode for what I've tried:</p>
  
  <pre><code>    fig1 = plt.figure(1, facecolor='white')
      figa = mySeparatePlottingFunc(...)
      figb = mySeparatePlottingFunc(...)
      figc = mySeparatePlottingFunc(...)
      figd = mySeparatePlottingFunc(...)
      fig1.add_subplot(411, figure=figa)
      fig1.add_subplot(412, figure=figb)
      fig1.add_subplot(413, figure=figc)
      fig1.add_subplot(414, figure=figd)
      fig1.show()
  </code></pre>
  
  <p>Sadly, however, this fails.  I know for a fact the individual plots returned from the function invocations are viable--I did a figa.show(),...,figd.show() to confirm that they are OK.  What I get for the final line in the above code block--fig1.show()--is 
  a collection of four empty plots that have frames and x- and y- tickmarks/labels.</p>
  
  <p>I've done quite a bit of googling around, and experimented extensively, but it's clear that I've missed something that is either really subtle, or embarrassingly obvious (I'll be happy for it to be the latter as long as I can get un-stuck).</p>
  
  <p>Thanks for any advice you can offer!</p>