- array_map: documentation ( source)
- var_dump: documentation ( source)
- array_unshift: documentation ( source)
<?php
$matrix = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9],
];
array_unshift($matrix, null);
$matrix = call_user_func_array('array_map', $matrix);
$matrix = array_map('array_reverse', $matrix);
var_dump($matrix);