How to convert json encoded PHP array to an array in Javascript?

I am fetching a JSON encoded array using AJAX from a PHP file, but in JavaScript I need to use it as an array, how can I create an array in Javascript?

My AJAX call to PHP File:

  $.ajax({
    type:"POST",
    url:"ajaxfetch.php",
    success:function(result){
            alert(result);
             }
    });

ARRAY Created in PHP File :

Array
(
    [0] => Array
        (
            [id] => 4

            [deviceID] => xyz123
            [latitude] =>  -33.80010128657071
            [longitude] => 151.28747820854187
            [altitude] => 34.78788787
            [createdDate] => 2013-08-15 23:00:00
            [delete] => 0
        )

    [1] => Array
        (

            [id] => 5
            [deviceID] => jdkfhjskh344
            [latitude] => -33.950198
            [longitude] => 151.259302
            [altitude] => 76.44455
            [createdDate] => 2013-08-15 21:50:42
            [delete] => 0
        )

    [2] => Array

        (
            [id] => 1
            [deviceID] => abc223
            [latitude] => -33.890542
            [longitude] => 151.274856
            [altitude] => 21.4454455
            [createdDate] => 2013-08-15 20:00:00
            [delete] => 0
        )


)

I json encoded this array in PHP but AJAX retrieved it and is outputted in a string.

ABOVE ARRAY json encode as given below:

$data = array();

$data = $locate_obj->getAllDeviceLocation();


echo json_encode($data);

Output of json_encode

[{"id":"4","deviceID":"xyz123","latitude":" -33.80010128657071","longitude":"151.28747820854187","altitude":"34.78788787","createdDate":"2013-08-15 23:00:00","delete":"0"},{"id":"5","deviceID":"jdkfhjskh344","latitude":"-33.950198","longitude":"151.259302","altitude":"76.44455","createdDate":"2013-08-15 21:50:42","delete":"0"},{"id":"1","deviceID":"abc223","latitude":"-33.890542","longitude":"151.274856","altitude":"21.4454455","createdDate":"2013-08-15 20:00:00","delete":"0"}]

I'm looking for the way I can create an array in Javascript with the output I recieve in ajax response, so that I can come up with an array of format:

var locations = [
      ['Bondi Beach', -33.890542, 151.274856, 4],
      ['Coogee Beach', -33.923036, 151.259052, 5],
      ['Cronulla Beach', -34.028249, 151.157507, 3],
      ['Manly Beach', -33.80010128657071, 151.28747820854187, 2],

      ['Maroubra Beach', -33.950198, 151.259302, 1]
    ];

Answer

There are three solution to this problem:

If you want to modify the structure on the client side, have a look at Access / process (nested) objects, arrays or JSON.