title: Scaleable, draggable box on plots that can select data
body: <p>Here's the setup:</p>
  
  <p>I've got a graphical plot of data, and I'm trying to find if it's feasible to try to put a box on the figure that can be moved and changed in width and return some values like percentage of and area under the curve. It looks something like this:</p>
  
  <p><img src="https://i.stack.imgur.com/9adyK.jpg" alt="Example"></p>
  
  <p>Any suggestions on where to start? My feeling was that it might be doable using a more GUI'd interface versus a standard plot.</p>