- var_dump: documentation ( source)
- array_column: documentation ( source)
<?php
$arr1 = array(
1=>'val1',
2=>'val2',
);
$arr2 = array(
1=>'num1',
2=>'num2',
);
$array = array($arr1, $arr2);
$newArr = array(array_column($array, 0), array_column($array, 1));
var_dump($newArr);