How to count the total keys in an array based on the value of that key
<p>This might be a basic question, but I am not getting any efficient way to do this. Suppose I have an array of multiple objects containing multiple key value like this. Now, I want the total count of <code>grActual</code> whose value is 16- Jan-13.I can iterate the array, and create a new array with key <code>grAcutal</code> and then I can count. Is there any other way to do that?</p>

<pre><code>    (
    {
    gIActual = "17-Jan-13";
    grActual = "16-Jan-13";
},
    {
    gIActual = "18-Jan-13";
    grActual = "16-Jan-13";
},
    {
    gIActual = "16-Jan-13";
    grActual = "16-Jan-13";      
},
    {
    gIActual = "16-Feb-13";
    grActual = "16-Jan-13";
})  
</code></pre>