title: iPhone 3.0 Compass: how to get a heading?
body: <p>I'm relatively new to Objective-C and really don't know much about it yet, so I apologise for what is probably a really amateurish question.</p>
  
  <p>I'm trying to get the magnetic heading from CLHeading and CLLocationDirection.  However I'm getting compile errors for this line of code:</p>
  
  <pre><code>locationLabel.text = [[[location course] magneticHeading] stringValue];
  </code></pre>
  
  <p>The errors are:</p>
  
  <pre><code>warning: invalid receiver type 'CLLocationDirection'  
  error: cannot convert to a pointer type
  </code></pre>
  
  <p>I don't really understand what I'm doing wrong here.  Please help!</p>