Witam, panowie mam takie dane wyjsciowe:

[PHP] pobierz, plaintext 
array:5 [▼
  0 => {#1565 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "444x142x6"
    +"intQuantityNeeded": "1"
  }
  1 => {#1563 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "444x142x6"
    +"intQuantityNeeded": "4"
  }
  2 => {#1561 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "748x370.5x6"
    +"intQuantityNeeded": "2"
  }
  3 => {#1560 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "900x256x6"
    +"intQuantityNeeded": "2"
  }
  4 => {#1559 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "900x256x6"
    +"intQuantityNeeded": "2"
  }
]
[PHP] pobierz, plaintext 

potrzebuje zsumowac intQuantityNeeded po strProductColourName (bo kolor moze byc inny a wtedy nie moge juz sumowac) oraz strCenterPanelSize:

[PHP] pobierz, plaintext 
array:5 [▼
  0 => {#1565 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "444x142x6"
    +"intQuantityNeeded": "5"
  }
  1 => {#1561 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "748x370.5x6"
    +"intQuantityNeeded": "2"
  }
  2 => {#1560 ▼
    +"strProductColourName": "English Oak"
    +"strCenterPanelSize": "900x256x6"
    +"intQuantityNeeded": "4"
  }
 
]
[PHP] pobierz, plaintext 

Ma ktos jakis pomysl? Z gory dzieki bo juz nie mam pomyslu.

Nie wiem w jakim języku masz te dane wejściowe, ale pytanie zadajesz w dziale PHP więc finalnie masz je chyba w zwykłej tablicy? Jeżeli tak, to lecisz po niej i sumujesz co potrzeba, poniżej przykład i wyniki (nie wiem czemu liczby masz podane jako string ale niech i tak będzie):

[PHP] pobierz, plaintext 
<?php
$input = [
  0 => [
    "strProductColourName" => "English Oak",
    "strCenterPanelSize" => "444x142x6",
    "intQuantityNeeded" => "1"
  ],
  1 => [
    "strProductColourName" => "English Oak",
    "strCenterPanelSize" => "444x142x6",
    "intQuantityNeeded" => "4"
  ],
  2 => [
    "strProductColourName" => "English Oak",
    "strCenterPanelSize" => "748x370.5x6",
    "intQuantityNeeded" => "2"
  ],
  3 => [
    "strProductColourName" => "English Oak",
    "strCenterPanelSize" => "900x256x6",
    "intQuantityNeeded" => "2"
  ],
  4 => [
    "strProductColourName" => "English Oak",
    "strCenterPanelSize" => "900x256x6",
    "intQuantityNeeded" => "2"
  ]
];
 
foreach($input as $value){
  $sumaColor[$value['strProductColourName']] = isSet($sumaColor[$value['strProductColourName']]) ? $sumaColor[$value['strProductColourName']] + $value['intQuantityNeeded'] : $value['intQuantityNeeded'];
  $sumaPanel[$value['strCenterPanelSize']] = isSet($sumaPanel[$value['strCenterPanelSize']]) ? $sumaPanel[$value['strCenterPanelSize']] + $value['intQuantityNeeded'] : $value['intQuantityNeeded'];
}
 
var_dump($sumaColor); 
/**
* array (size=1)
*   'English Oak' => int 11
*/
 
var_dump($sumaPanel); 
/**
* array (size=3)
*	  '444x142x6' => int 5
*	  '748x370.5x6' => string '2' (length=1)
*	  '900x256x6' => int 4
*/
?>
[PHP] pobierz, plaintext 

Ja bym pojechał z array_reduce:

[PHP] pobierz, plaintext 
$result = array_reduce(
    $data,
    function (array $carry, array $item): array {
        $matchingItemIndex = array_key_first(array_filter($carry, fn(array $groupedItem): bool => (
            $groupedItem['strProductColourName'] === $item['strProductColourName']
            && $groupedItem['strCenterPanelSize'] === $item['strCenterPanelSize']
        )));
 
        if ($matchingItemIndex !== null) {
            $carry[$matchingItemIndex]['intQuantityNeeded'] += $item['intQuantityNeeded'];
        } else {
            $carry[] = $item;
        }
 
        return $carry;
    },
    []
);
[PHP] pobierz, plaintext 

Dzieki Smok. Bardzo mi pomogles.