Filter 2 dimensional array

Question

I have a array that looks a bit like this

array(
    [0] => array(
        ['id'] => 29
        ['name'] => john
        )
    [1] => array(
        ['id'] => 30
        ['name'] => joe
        ) 
    [2] => array(
        ['id'] => 29
        ['name'] => jake
        ) 
)

And that goes on for a while.

I've found the question elsewhere (here) and (here) But neither works.

With the first one I get the following array

array(
    [0] => 29
    [1] => jake
)

And with te second one it only filters out exact duplicates and not duplicates with jus the same id.

I want all the duplicates with the same id removed from the array, how do I do that?

So your result is expected to only contain `joe`? – deceze Jun 19 '15 at 15:01 — deceze, Jun 19 '15 at 15:01
@deceze no, `john` and `joe`. – Liam de Haas Jun 19 '15 at 15:12 — Liam de Haas, Jun 19 '15 at 15:12

score 5 · Answer 1 · answered Jun 19 '15 at 15:15

5

Simple with PHP >= 5.5.0:

$result = array_column($array, null, 'id');

Optionally:

$result = array_values(array_column($array, null, 'id'));

answered Jun 19 '15 at 15:15

AbraCadaver

78,200
7
66
87

score 4 · Accepted Answer · answered Jun 19 '15 at 15:13

4

$filteredUsers = [];
foreach ($users as $user) {
    $filteredUsers[$user['id']] = $user;
}

// optionally:
// $filteredUsers = array_values($filteredUsers);

answered Jun 19 '15 at 15:13

deceze

510,633
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743
889

I have in fact posted variations on this answer many many times already, but I can't find any of them at the moment... – deceze Jun 19 '15 at 15:16

Federkun · Answer 3 · 2015-06-19T15:12:04.390

If you want delete the duplicate and leave one alone:

$array = array(
    array(
        'id' => 29,
        'name' => 'john'
    ),
    array(
        'id' => 30,
        'name' => 'joe'
    ),
    array(
        'id' => 29,
        'name' => 'jake'
    ) 
);

$filter = [];
$array = array_filter($array, function($a) use (&$filter) {
    $ret = !isset($filter[$a['id']]);
    $filter[$a['id']] = true;

    return $ret;
});

Demo.

Otherwise:

$duplicate = array_count_values(array_map(function($i) {
   return $i['id'];
}, $array));

$array = array_filter($array, function($a) use ($duplicate) {
    return $duplicate[$a['id']] <= 1;
});

var_dump($array);

This will print:

array(1) {
  [1]=>
  array(2) {
    ["id"]=>
    int(30)
    ["name"]=>
    string(3) "joe"
  }
}

Filter 2 dimensional array

3 Answers3