title: Get all values of a specific column in a multidimensional array
body: <p>I have a multidimensional array, that has say, x number of columns and y number of rows.</p>
  
  <p>I want specifically all the values in the 3rd column.</p>
  
  <p>The obvious way to go about doing this is to put this in a for loop like this</p>
  
  <pre><code>for(i=0;i&lt;y-1;i++)
  {
     $ThirdColumn[] = $array[$i][3];
  }
  </code></pre>
  
  <p>but there is an obvious time complexity of O(n) involved here. Is there a built in way for me to simply extract each of these rows from the array without having to loop in.</p>
  
  <p>For example (this does not work offcourse)</p>
  
  <pre><code>$ThirdColumn  = $array[][3]
  </code></pre>