Consolidate single multi-dimensional array by individual key of nested array PHP-CodePudding

The question makes this sound way more complicated than it is. I have poured too much time into trying every variation of array_merge, etc. Maybe this is easy for someone:

I have a multi-dimensional array:

$array = [
        0 => [
            'class' => 'A',
            'jon' => '0.50'
        ],
        1 => [
            'class' => 'B',
            'jon' => '0.40'
        ],
        2 => [
            'class' => 'A',
            'steve' => '0.90'
        ],
        3 => [
            'class' => 'B',
            'steve' => '0.80'
        ]
    ];

The keys (0,1,2,3) aren't important. I want to consolidate this array based on the class key within each nested array. Desired outcome:

$outcome = [
        0 => [
            'class' => 'A',
            'jon' => '0.50',
            'steve' => '0.90'
        ],
        1 => [
            'class' => 'B',
            'jon' => '0.40',
            'steve' => '0.80'
        ]
    ];

Working in PHP7.4 if relevant, but I doubt it. Thanks in advance.

CodePudding user response：

Something like this would probably work.

$sorted = [];
foreach ($array as $item) {
    $sorted[$item['class']] = array_merge($item, $sorted[$item['class']] ?? []);
}

Iterating each item and plucking out the class property to make the key of the array
We then either merge the elements already attached to that key with the current item or thanks to the null coalescing operator - use an empty array