title: Assigning ranks of elements relative to the other elements of a row in a matrix
body: <p>How to assign ranks of elements relative to the other elements of a row in a matrix?
  For example, I'd like to convert:</p>
  
  <pre><code>A = [1 2 4 0; 
       2 3 1 8; 
       9 1 2 3];
  </code></pre>
  
  <p>into:</p>
  
  <pre><code>[1 2 4 3; 
   2 3 1 4; 
   4 1 2 3]
  </code></pre>