How to compare the two dates in PHP

function compare_date ($date_one,$date_two){


//your input should be dd/mm/yy
$arr_date_one= explode ("/", $date_one);
$arr_date_two= explode ("/", $date_two);
//remove the '/'


$days_one = $arr_date_one[0];
$months_one = $arr_date_one[1];
$year_one = $arr_date_one[2];

$days_two = $arr_date_two[0];
$months_two = $arr_date_two[1];
$year_two = $arr_date_two[2];

$date_one_jul = gregoriantojd($days_one , $months_one , $year_one );
$date_two_jul = gregoriantojd($days_two , $months_two , $year_two );

return $date_one_jul - $date_two_jul ;
}

//out put will be  +/- value depend on your parameters