Selection sort in PHP

gistfile1.php

<?php
$array = range(1, 20);
shuffle($array);

var_dump($array);
var_dump(selectionsort($array));

function selectionsort($array)
{
	$size = count($array);
	for ($i = 0; $i < $size; $i++) {
		$min_index = $i;
		for ($j = $i + 1; $j < $size; $j++) {
			if ($array[$j] < $array[$min_index]) $min_index = $j; 
		}
		list($array[$i], $array[$min_index]) = array($array[$min_index], $array[$i]);
	}
	return $array;
}