title: extrapolating data with numpy/python
body: <p>Let's say I have a simple data set. Perhaps in dictionary form, it would look like this:</p>
  
  <p><code>{1:5, 2:10, 3:15, 4:20, 5:25}</code></p>
  
  <p>(the order is always ascending).
  What I want to do is logically figure out what the next point of data is most likely to be. In the case, for example, it would be <code>{6: 30}</code></p>
  
  <p>what would be the best way to do this?</p>