title: Sort data based on another column
body: <p>Given the following table</p>
  
  <pre><code>   A       B     C        D
     fred    1     wilma    6
     wilma   6     fred     1
     barney  3     bill     4
     bill    4     steve    6
     bob     5     george   7
                   barney   3
                   bob      5
  </code></pre>
  
  <p>Is it possible to sort C and D to match the arrangement in A and B without sorting A and B? </p>