php - multidimensional array duplicates merge -

i have multidimensional array , want combine duplicates same data, example have array fields:

    array(5) {   [0]=>   array(2) {     ["data"]=> string(10) "05-30-2013"     ["link"]=> string() "unions"   }   [1]=>   array(2) {     ["data"]=> string(10) "06-03-2013"     ["link"]=> string() "potatoes"   }   [2]=>   array(2) {     ["data"]=> string(10) "06-03-2013"     ["link"]=> string() "apple"   }   [3]=>   array(2) {     ["data"]=> string(10) "06-03-2013"     ["link"]=> string() "banana"   }   [4]=>   array(2) {     ["data"]=> string(10) "05-30-2013"     ["link"]=> string() "pear"   }   } 

and want combine same dates in one.

array(2) {   [0]=>   array(2) {     ["data"]=> string(10) "05-30-2013"     ["link"]=> string() "unions,pear"   }   [1]=>   array(2) {     ["data"]=> string(10) "06-03-2013"     ["link"]=> string() "potatoes,apple,banana"   }   } 

how do this? thanks

$arr = array (    0 => array (      "data" => "05-30-2013",      "link" => "unions"),    1 => array (      "data" => "06-03-2013",      "link" => "potatoes"),    2 => array (      "data" => "06-03-2013",      "link" => "apple"),    3 => array (      "data" => "06-03-2013",      "link" => "banana"),    4 => array (      "data" => "05-30-2013",      "link" => "pear")); $out = array(); foreach ($arr $key => $value){     if (array_key_exists($value['data'], $out)){         $out[$value['data']]['link'] .= ', '.$value['link'];     } else {         $out[$value['data']] = array('data' => $value['data'], 'link' => $value['link']);     } } $out = array_values($out); print_r($out);