title: How to arrange nested subplots in Matplotlib?
body: <p>I have 3 plots arranged vertically with the following code:</p>
  
  <pre><code>plt.figure(1)
  plt.subplot(311)
  plt.plot(z2, 'blue')
  plt.plot(mid2, 'orange')
  plt.plot(z3, 'red')
  plt.plot(mid3, 'orange')
  plt.subplot(312)
  plt.plot(z)
  plt.plot(mid)
  plt.subplot(313)
  plt.plot(proportional, "black")
  </code></pre>
  
  <p>But what I want to do is adding another plot next to the first plot(311). I mean I want to have two plots inside the first row, then one plot inside next two rows as before(I like to show z2,mid2 in one plot and z3,mid3 in other plot next to that, both inside the first row). If is it possible, how can I do that?</p>