title: find max difference between elements in vector
body: <p>I want to evaluate the difference (susbtraction) between all elements in a vector and have the maximum as a result.</p>
  
  <p>For example with </p>
  
  <pre><code>[1 3 7]
  </code></pre>
  
  <p>the diffs are 2, 4 and 6, so that the result should be 6.</p>
  
  <p>How can I do that with matlab in a clever way?</p>