title: valid way to calculate angle between 2 CLLocations?
body: <p>Is this a valid way to calculate an angle (in radians) from one CLLocation to another?</p>
  
  <pre><code>-(float)angleFromLocation:(CLLocationCoordinate2D)start toLocation:(CLLocationCoordinate2D)end {
  float deltaX = start.latitude - end.latitude;
  float deltaY = start.longitude - end.longitude;
  float ang = atan2(deltaY, deltaX);
  
  return ang;}
  </code></pre>
  
  <p>Please advise!</p>
  
  <p>Any help will be much appreciated.</p>