title: How to plot complex number
body: <p>I am trying to plot a point in the complex number plane like that: </p>
  
  <pre><code>from matplotlib.pyplot import*
  i = complex(3,1)*2
  plot(i,'b.')
  show()`
  </code></pre>
  
  <p>However the resulting plot displays the point <code>z=3+0i</code>. How can I make it take the imaginary component into account?</p>