PHP Round Numbers

Round Numbers

<?
$numbers = "0 7 0 0 10";
$test = explode(" ", $numbers);
function big($numbers) {
	$var = "0";
	$test = explode(" ", $numbers);
	for ($i=0; $i<=count($test)-1; $i++)
	$ch = $test[$i];
	if ($var < $ch) $var = $ch;
	return $var;
}
echo big($numbers);
?>