title: Keep the gap between two datasets in matplotlib
body: <p>I have two datasets</p>
  
  <pre><code>firstX = [0, 1, 2, 3, 4, 5, 6] # X Axis 
  firstY = [10, 10, 20, 30, 40, 60, 70] # Y Axis
  secondX = [9, 10, 11, 12, 13, 14, 15] # X Axis
  secondY = [40, 20, 60, 11, 77, 12, 54] # Y Axis
  </code></pre>
  
  <p>I want to plot these two datasets in the same chart but without connecting them together. As you can see, there is a disconnection between them (in X axis, 7 and 8 are missing). When I concat them, matplotlib will try to connect the last point of the first dataset <code>(6, 70)</code> with the first point of the second dataset <code>(9, 40)</code>. I would like to know how to avoid this behavior</p>