array_multisort
Syntax:bool array_multisort ( array &$arr [, mixed $arg = SORT_ASC [, mixed $arg = SORT_REGULAR [, mixed $... ]]] )
Description:Sort multiple or multi-dimensional arrays
<?php
$ar1 = array(10, 100, 100, 0);
array_multisort($ar1);
print_r($ar1);
?>
OUTPUT
Array (
[0] => 0
[1] => 10
[2] => 100
[3] => 100
)