เช็คค่าซ้ำ php array นำผลรวมค่า duplicate ซ้ำมารวมกัน รบกวนช่วยชี้แนะหน่อยครับ

sort($arrayName); 
$new = array(); 

foreach ($arrayName as $k => $v) { 
    if (array_key_exists($k, $new)) { 
        $new[$k] += $v; 
    } else { 
        $new[$k] = $v; 
    } 
}

function sumoutarray($array,$fnumber,$money){
		$result = array ();
		foreach ( $array as $item ) {
			$id = $item->$fnumber;
			if (isset ( $result [$id] )) {
				$result [$id] +=$item->$money;
			} else {
				$result [$id] = $item->$money;
			}
		}
		return $result;
	}

$arrayName = array('a' =>'100','b'=>'20','a'=>'10','z'=>'50','b'=>'200','x'=>'500','z'=>'60');
print_r( $arrayName );