find duplicates value with their keys - php

Question

My array is like this,
$options = Array
(
[0] => Array
(
[value] => 180
[label] => Nokia
)
[1] => Array
(
[value] => 2341
[label] => Suisses
)
[2] => Array
(
[value] => 143
[label] => Nokia
)
[3] => Array
(
[value] => 2389
[label] => 3D Pop Art
)
)
and i want output as,
Array(
[0] => Array
(
[value] => 180
[label] => Nokia
)
[2] => Array
(
[value] => 143
[label] => Nokia
)
)
Can anyone suggest me in this.

Answer 1

You can try something like this:
$options = [
0 => [
'value' => 180,
'label' => 'Nokia'
],
1 => [
'value' => 2341,
'label' => 'Suisses'
],
2 => [
'value' => 143,
'label' => 'Nokia'
],
3 => [
'value' => 2389,
'label' => '3D Pop Art'
],
];
$labels = [];
$duplicates = [];
foreach ($options as $option) {
if (!empty($duplicates[$option['label']])) {
$duplicates[$option['label']][] = $option;
}
if (empty($labels[$option['label']])) {
$labels[$option['label']] = $option;
} else {
$duplicates[$option['label']] = [
$labels[$option['label']],
$option
];
}
}

Answer 2

It seems you are looking for group by 'label'
foreach($options as $v){
$c[$v['label']][] = $v['value'];
}
print_r($c);
Working example : https://3v4l.org/62dv0

Answer 3

The array_filter() function is what you are looking for:
<?php
$data = [
[
'value' => 180,
'label' => "Nokia"
],
[
'value' => 2341,
'label' => "Suisses"
],
[
'value' => 143,
'label' => "Nokia"
],
[
'value' => 2389,
'label' => "3D Pop Art"
]
];
$output = [];
array_walk($input, function($entry) use (&$output) {
$output[$entry['label']][] = $entry;
});
print_r(
array_filter(
$output,
function($entry) {
return count($entry) > 1;
}
)
);
The output obviously is:
Array
(
[Nokia] => Array
(
[0] => Array
(
[value] => 180
[label] => Nokia
)
[1] => Array
(
[value] => 143
[label] => Nokia
)
)
)
That output slightly differs from the one suggested by you. But it has the advantage that you can tell entries apart by the doubled label.