Date and Time difference function

/*///Find the difference (MYSQL DATETIME/DATE Format) 

function find_difference($start_date,$end_date){
list($date,$time) = explode(" ",$start_date);
if($time == NULL){$time = '00:00:00';}
$startdate = explode("-",$date);
$starttime = explode(":",$time);

list($date,$time) = explode(" ",$end_date);
if($time == NULL){$time = '00:00:00';}
$enddate = explode("-",$date);
$endtime = explode(":",$time);

//Get unix timestamp in seconds
$secons_dif = mktime($endtime[0],$endtime[1],$endtime[2],$enddate[1],$enddate[2],$enddate[0]) - mktime($starttime[0],$starttime[1],$starttime[2],$startdate[1],$startdate[2],$startdate[0]);

//We will return it in seconds, minutes, hours, days, weeks, months, years
//put the word floor before () to round to the nearest whole number.

$seconds = $secons_dif;
$minutes = ($secons_dif/60);
$hours = ($secons_dif/60/60);
$days = ($secons_dif/60/60/24);
$weeks = ($secons_dif/60/60/24/7);
$months = ($secons_dif/60/60/24/7/4);
$years = ($secons_dif/365/60/24/60);

return $days;
}*/