How to convert seconds into days hours minutes in PHP? (Time elapsed, just now, ago)

Use example :

echo time_elapsed_string('2013-05-01 00:22:35');
echo time_elapsed_string('@1367367755');# timestamp input
echo time_elapsed_string('2013-05-01 00:22:35',true);

Input can be any supported date and time format.

Output :

4 months ago
4 months,2 weeks,3 days,1 hour,49 minutes,15 seconds ago

Function :

function time_elapsed_string($datetime, $full =false){
    $now =newDateTime;
    $ago =newDateTime($datetime);
    $diff = $now->diff($ago);

    $diff->w = floor($diff->d /7);
    $diff->d -= $diff->w *7;

    $string = array('y'=>'year','m'=>'month','w'=>'week','d'=>'day','h'=>'hour','i'=>'minute','s'=>'second',);foreach($string as $k =>&$v){if($diff->$k){
            $v = $diff->$k .' '. $v .($diff->$k >1?'s':'');}else{
            unset($string[$k]);}}if(!$full) $string = array_slice($string,0,1);return $string ? implode(', ', $string).' ago':'just now';}

http://stackoverflow.com/questions/1416697/converting-timestamp-to-time-ago-in-php-e-g-1-day-ago-2-days-ago/18602474#18602474