title: Mod operator in ios
body: <p>have been searching for a mod operator in ios, just like the <code>%</code> in c, but no luck in finding it. Tried the answer in this <a href="https://stackoverflow.com/questions/3731167/using-mod-operator-in-ios-app">link</a> but it gives the same error. 
  I have a float variable 'rotationAngle' whose angle keeps incrementing or decrementing based on the users finger movement. 
  Some thing like this:</p>
  
  <pre><code>if (startPoint.x &lt; pt.x) {
      if (pt.y&lt;936/2) 
          rotationAngle += pt.x - startPoint.x;
      else
          rotationAngle += startPoint.x - pt.x;   
      }
      rotationAngle = (rotationAngle % 360);
  }
  </code></pre>
  
  <p>I just need to make sure that the rotationAngle doesnot cross the +/- 360 limit.
  Any help any body. 
  Thanks </p>