Filter Array Duplicates On Associative Value
<p>I've got an array:</p>

<pre><code>(
[0]
   (
      [room_num] =&gt; 1
      [is_event] =&gt; true
      [date] =&gt; '01/01/2013'
   )
[1]
   (
      [room_num] =&gt; 2
      [is_event] =&gt; false
      [date] =&gt; ''
   )
[2]
   (
      [room_num] =&gt; 3
      [is_event] =&gt; false
      [date] =&gt; ''
   )
[3]
   (
      [room_num] =&gt; 1
      [is_event] =&gt; false
      [date] =&gt; ''
   )
)
</code></pre>

<p>What I'd like to do is filter the results so that where <code>is_event = true</code> supersedes <code>is_event = false</code>. My returned array would look like:</p>

<pre><code>(
[0]
   (
      [room_num] =&gt; 1
      [is_event] =&gt; true
      [date] =&gt; '01/01/2013'
   )
[1]
   (
      [room_num] =&gt; 2
      [is_event] =&gt; false
      [date] =&gt; ''
   )
[2]
   (
      [room_num] =&gt; 3
      [is_event] =&gt; false
      [date] =&gt; ''
   )
)
</code></pre>

<p>Sort of like array_unique except ON a certain value. </p>

<p>Is there a built in function for this? </p>
