title: How can I efficiently remove zeroes from a (non-sparse) matrix?
body: <p>I have a matrix:</p>
  
  <pre><code>x = [0 0 0 1 1 0 5 0 7 0];
  </code></pre>
  
  <p>I need to remove all of the zeroes, like so:</p>
  
  <pre><code>x = [1 1 5 7];
  </code></pre>
  
  <p>The matrices I am using are large (1x15000) and I need to do this multiple times (5000+), so efficiency is key!</p>