title: Drawing a polygon around groups of datapoints in MATLAB
body: <p>I have a set of datapoints each of which belongs to a certain cluster (group).  I need to draw a polygon around each of these clusters.  Does anyone knows how to do it? </p>
  
  <p>It doesn't matter if I use or not use the actual datapoints for drawing the polygon. I just need them to be wrapped in a polygon.</p>