PHP function to get difference between two times

Time Difference

/**
 * returns the difference between two times
 * @param 	string	$start 	the starting time for comparison
 * @param		string 	$end	the ending time for comparison
 * @return 	array 	an array is populated with the time difference
 */
function timediff($start, $end) {
    $timediff = $end - $start;
    $days = intval($timediff / 86400);
    $remain = $timediff % 86400;
    $hours = intval($remain / 3600);
    $remain = $remain % 3600;
    $mins = intval($remain / 60);
    $secs = $remain % 60;

    $output = array();
    $output['days'] = $days;
    $output['hours'] = $hours;
    $output['minutes'] = $minutes;
    $output['seconds'] = $seconds;
    $output['full'] = $days . 'days ' . $hours . 'hrs ' . $mins . 'mins ' . $secs . 'sec ';
    return $output;
}