public static function quicksort($arr, $field = 'label', $sort = 'asc')
{
if (count($arr) <= 1) {
return $arr;
}
$piv = $arr[0];
$x = $y = array();
$len = count($arr);
$i = 1;
while ($i < $len) {
if ($sort == 'asc' && $arr[$i][$field] <= $piv[$field]) {
$x[] = $arr[$i];
} else {
if ($sort == 'desc' && $arr[$i][$field] > $piv[$field]) {
$x[] = $arr[$i];
} else {
$y[] = $arr[$i];
}
}
++$i;
}
return array_merge(UtilsHelper::quicksort($x, $field, $sort), array($piv), UtilsHelper::quicksort($y, $field, $sort));
}
