Function to determine whether a php array is an index array

/**
* Check whether to index the array
* edit bbs.it-home.org
*/
function is_assoc($array) {
if(is_array($array)) {
$keys = array_keys($array) ;
return $keys != array_keys($keys);
}
return false;
}
//Call example
echo is_assoc($array)?'Index array':'Not Index array';
?>