Convert multidimensional array into single array

Question

I have an array which is multidimensional for no reason

/* This is how my array is currently */
Array
(
[0] => Array
    (
        [0] => Array
                


        

Answer 1

This single line would do that:

$array = array_column($array, 'plan');

The first argument is an array | The second argument is an array key.

For details, go to official documentation: https://www.php.net/manual/en/function.array-column.php.