title: Interpolate coordinate based data to produce a meshgrid
body: <p>Lets say I have data as follows: </p>
  
  <pre><code>data = {(1,3):22, (1,3.5):23, (1,4.5):25, ..., (1.5,3.3): 19, ... (4,4):100 }
  </code></pre>
  
  <p>where I have a set of coordinates and an associated value between 0 and 100. Lets say the coordinates represent houses in a suburb.</p>
  
  <p>How do I interpolate this data so as to create a <code>meshgrid</code> to use when plotting. </p>