PHP Creating a new type of array from an array

Question

I have the following array of data:

$data = array(
 0 => array(
   'firstname' => 'John',
   'lastname' => 'Doe'
 ),
 1 => array(
   'firstname' => 'Foo',
   'lastname' => 'Bar'
 )
)

And Id like to manipulate it to end up with this array:

$finalData = array(
 'firstname' => array('John','Foo'),
 'lastname' => array('Doe','Bar')
)

How do I accomplish this using PHP? Id love to learn about the PHP array methods if one can be used in this scenario.

Thanks!

Answer 1

This is too specialized for functions like array_map without shooting yourself in the foot. But you can easily do it with a foreach loop:

$finalData = array();
foreach ($data as $person) {
    $finalData['firstname'][] = $person['firstname'];
    $finalData['lastname'][] = $person['lastname'];
}

Answer 2

You will have to loop through $data to gather first names and last names separately. Unfortunately there is no standard php function that performs "array pluck".

Answer 3

Well, I don't think that something like that exist, but I think You should read docs on array functions

If You don't find anything, make something your own (probably with with array_map), and please answer your own question.

Answer 4

This gives what you want;

$new_data = array();
foreach ($data as $d) {
    $keys = array_keys($d);
    foreach ($keys as $k) {
        $new_data[$k][] = $d[$k];
    }
}
print_r($new_data);

Result;

Array
(
    [firstname] => Array
        (
            [0] => John
            [1] => Foo
        )

    [lastname] => Array
        (
            [0] => Doe
            [1] => Bar
        )

)