title: Fastest way of sorting multidimensional arrays in php
body: <pre><code>Array
  (
  [0] =&gt; Array
  (
  [t] =&gt; 81881
  [b] =&gt; 99494
  )
  [1] =&gt; Array
  (
  )
  ...
  ...
  )
  </code></pre>
  
  <p>I have a multidimensional array like above.The entries in this array would be ranging upto 20k. I want to sort this array acc. to "t" index without calling any external function. Any suggestions for improving the efficiency.</p>