title: Count occurrences of a value in a column of an array of object arrays
body: <p>Does anyone know how to count the occurrences of "photo" in this array:</p>
  
  <pre><code>    Array ( 
      [0] =&gt; stdClass Object ( [type] =&gt; photo [id] =&gt; 1404781893036 [created_time] =&gt; 2012-03-02T07:58:23+0000 ) 
      [1] =&gt; stdClass Object ( [type] =&gt; photo [id] =&gt; 14047818930362 [created_time] =&gt; 2012-03-01T14:58:53+0000 ) 
      [2] =&gt; stdClass Object ( [type] =&gt; status [id] =&gt; 1404781893036 [created_time] =&gt; 2012-03-01T09:49:40+0000 ) 
      [3] =&gt; stdClass Object ( [type] =&gt; status [id] =&gt; 14047818930362 [created_time] =&gt; 2012-03-01T09:36:04+0000 ) 
      [4] =&gt; stdClass Object ( [type] =&gt; photo [id] =&gt; 14047818930362 [created_time] =&gt; 2012-02-28T07:03:25+0000 ) 
      [5] =&gt; stdClass Object ( [type] =&gt; photo [id] =&gt; 1404781893036 [created_time] =&gt; 2012-02-27T09:15:34+0000 ) 
      [6] =&gt; stdClass Object ( [type] =&gt; photo [id] =&gt; 14047818930362 [created_time] =&gt; 2012-02-27T07:32:13+0000 ) 
      [7] =&gt; stdClass Object ( [type] =&gt; status [id] =&gt; 1404781893036 [created_time] =&gt; 2012-02-25T09:36:57+0000 )
      [8] =&gt; stdClass Object ( [type] =&gt; photo [id] =&gt; 1404781893036 [created_time] =&gt; 2012-02-23T08:46:43+0000 ) 
      [9] =&gt; stdClass Object ( [type] =&gt; status [id] =&gt; 1404781893036 [created_time] =&gt; 2012-02-22T21:04:30+0000 ) 
      [10] =&gt; stdClass Object ( [type] =&gt; status [id] =&gt; 1404781893036 [created_time] =&gt; 2012-02-21T20:38:27+0000 )
      [11] =&gt; stdClass Object ( [type] =&gt; photo [id] =&gt; 1404781893036 [created_time] =&gt; 2012-02-21T07:22:44+0000 ) 
      [12] =&gt; stdClass Object ( [type] =&gt; status [id] =&gt; 14047818930362 [created_time] =&gt; 2012-02-20T08:32:46+0000 ) 
      [13] =&gt; stdClass Object ( [type] =&gt; status [id] =&gt; 1404781893036 [created_time] =&gt; 2012-02-17T15:00:11+0000 ) )
  </code></pre>