array_cross

array_cross.php

<?php 


function array_cross() {
	
	$arrays = func_get_args();
	
	//force indexed arrays, stripping any extra keys.
	array_walk($arrays, function (&$n) {
		return is_array($n) ? array_values($n) : null;
	});
	
	//make sure we're only dealing with arrays
	$arrays = array_filter($arrays);
	$arrays = array_values($arrays);
	
	//if there aren't at least two valid inputs, there is nothing more to be done.
	if (count($arrays) < 2) return $arrays;
	
	//collect the sizes of the arrays
	$counts = array_map(function ($n) {
		return count($n);
	}, $arrays);
	
	$maxLength = max($counts);
	
	$vertex = count($arrays);
	
	$results = array_fill(0, $vertex, array());
	for ($i=0;$i<$maxLength;$i++) {
		for ($j=0;$j<$vertex;$j++) {
			$results[$i][$j] = isset($arrays[$j][$i]) ? $arrays[$j][$i] : null;
		}
	}
	
	return $results;
}


$a = Array('a', 'b', 'c', 'd');
$b = Array('e', 'f', 'g', 'h', 'z', 'x');
$c = Array('i', 'j', null,'k', 'l');
$d = array_cross($a, $b, $c);

print_r($d);

gistfile1.txt

Array
(
    [0] => Array
        (
            [0] => a
            [1] => e
            [2] => i
        )

    [1] => Array
        (
            [0] => b
            [1] => f
            [2] => j
        )

    [2] => Array
        (
            [0] => c
            [1] => g
            [2] => 
        )

    [3] => Array
        (
            [0] => d
            [1] => h
            [2] => k
        )

    [4] => Array
        (
            [0] => 
            [1] => z
            [2] => l
        )

    [5] => Array
        (
            [0] => 
            [1] => x
            [2] => 
        )

)