笛卡尔积算法，二维数组矩阵算法PHP

递归实现

$arr	= array(
	array(1),
	array(2,3),
	array(4,5,6)
);
fun($arr);
print_r($res);
function fun($arr, $tmp = array())
{
	foreach(array_shift($arr) AS $v)
	{
		$tmp[]	= $v;
		if($arr)
		{
			fun($arr, $tmp);
		}
		else
		{
			$GLOBALS["res"][]	= $tmp;
		}
		array_pop($tmp);
	}
}

foreach，遍历每个元素元素，进行递归。

如：

1,2      4 5 6   => 1,2,4     1,2,5    1,2,6

1,3      4 5 6   => 1,3,4     1,3,5    1,3,6

http://bbs.csdn.net/topics/380239639

举例：

$arr = array(
    "a"=>array("a1","a2","a3"),
    "b"=>array("b1","b2","b3"),
    "c"=>array("c1","c2","c3"),

	//..........多行......
);

fun($arr);
//print_r($res);

echo "<table width="150px" border="1">";
$j=0;
	echo "<tr>";
	echo "<td>序号</td>";
	foreach($arr as $k=>$v)
	{		
		echo "<td>".$k."</td>";
	}	
	echo "</tr>";
foreach($res as $v)
{
	echo "<tr>";
	$i=0;
	$j++;
	echo "<td>".$j."</td>";
	foreach($arr as $value)
	{		
		echo "<td>".$v[$i]."</td>";
		$i++;
	}	
	echo "</tr>";
}
echo "</table>";

function fun($arr, $tmp = array())
{
	
	foreach(array_shift($arr) AS $v)
	{
		$tmp[]	= $v;		
		if($arr)
		{
			fun($arr, $tmp);
		}
		else
		{
			$GLOBALS["res"][]	= $tmp;
		}
		array_pop($tmp);
	}
}

exit;

非递归：（其实也类似递归）

$arr = array(
array("a1","a2",),
array("c1","c2",),
array("d1","d2","d3"),
//......省略其它元素（也可以是数组），
);
$r = Descartes( $arr );

print_r($r);
function Descartes() {
	$t = func_get_args();
	if(func_num_args() == 1) return call_user_func_array( __FUNCTION__, $t[0] );
	$a = array_shift($t);
	if(! is_array($a)) $a = array($a);
	$a = array_chunk($a, 1);
		do {
			$r = array();
			$b = array_shift($t);
			if(! is_array($b)) $b = array($b);
			foreach($a as $p)
			foreach(array_chunk($b, 1) as $q)
			$r[] = array_merge($p, $q);
			$a = $r;
		}
		while($t);
	return $r;
}

exit;