Accumulate in array php

Question

I have an array which is multidimensional

Array ( 
    [0] => Array ( [id] => 2 [id_product_attribute] => 9 ) 
    [1] => Array ( [id] => 2 [id_product_attribute] => 10 ) 
    [2] => Array ( [id] => 2 [id_product_attribute] => 8 ) 
    [3] => Array ( [id] => 3 [id_product_attribute] => 50 ) 
)

I want to convert this array into this form

Array ( 
    [0] => Array ( [id] => 2 [id_product_attribute] => Array(9,10,8) ) 
    [1] => Array ( [id] => 3 [id_product_attribute] => Array (50) )
)

what is the actual logic for it? it doesn't make any sense how you group those items without you explaining what you're trying to do. — Kasia Gogolek, Mar 02 '18 at 11:25
the id was 2 for all the rows before the edit, hence my question. — Kasia Gogolek, Mar 02 '18 at 11:36
Possible duplicate of [php array group](https://stackoverflow.com/questions/12706359/php-array-group) — lsl, Mar 02 '18 at 14:39

score 1 · Accepted Answer · answered Mar 02 '18 at 11:41

Loop throught the first array and merge the values into the second one, then use array_values to order the first level array: (Sandbox)

$orig = array( 
    0 => array( 'id' => 2, 'id_product_attribute' => 9 ),
    1 => array( 'id' => 2, 'id_product_attribute' => 10 ),
    2 => array( 'id' => 2, 'id_product_attribute' => 8 ),
    3 => array( 'id' => 3, 'id_product_attribute' => 50 )
);

$array = [];
foreach ($orig as $o) {
    if (!isset($array[$o['id']])) {
        $array[$o['id']] = ['id' => $o['id'], 'id_product_attribute' => []];
    }

    $array[$o['id']]['id_product_attribute'][] = $o['id_product_attribute'];
}

// to get the first array with indexes 0,1...
$result = array_values($array);

print_r($result);

Accumulate in array php

1 Answers1