hash array to function

[tashbee]

Hello all,

I have a multidimentional array

$array_name[value?][]
$array_name[value?][]
$array_name[value?][].... etc

which I would like to compare using the array_intersect comand.

in long hand would look like
$result = array_intersect($array_name[value?],$array_name[value2],....etc);

Is there a realy neat way of passing these changing number of arrays to a function.

I hope I made sense, and if I have asked an old question I have looked honest !!

Thank you in advance

Thomas Ashbee

[majik-sheff]

If I understand you correctly, this is probably what you want.

<?PHP
$a = array(array(1, 2, 3, 4, 5, 6, 7, 8, 9),
array(1, 2, 3, 4, 5,),
array(1, 3, 4, 5, 7),
array(1, 4, 5));

$intersect = array_map("cumulative_intersect", $a);
print_r(cumulative_intersect());

function cumulative_intersect($in = null) {
	static $accumulator = array();
	if (is_null($in)) {
		return($accumulator);
	}
	if (sizeof($accumulator) == 0) {
		$accumulator = $in;
	}
	$accumulator = array_intersect($accumulator, $in);
	return($accumulator);
}

?>

Returns:

Array
(
[0] => 1
[3] => 4
[4] => 5
)

[majik-sheff]

Slight correction, that code would mess up your original array. This is fixed:

<?PHP
$a = array(array(1, 2, 3, 4, 5, 6, 7, 8, 9),
array(1, 2, 3, 4, 5,),
array(1, 3, 4, 5, 7),
array(1, 4, 5));

$intersect = array_map("cumulative_intersect", $a);
print_r(cumulative_intersect());

function cumulative_intersect($in = null) {
	static $accumulator = array();
	if (is_null($in)) {
		return($accumulator);
	}
	if (sizeof($accumulator) == 0) {
		$accumulator = $in;
	}
	$accumulator = array_intersect($accumulator, $in);
}

?>

[majik-sheff]

Sorry that function was kind of off-the-cuff. It doesn't properly handle when there are no results after an intersect. This fixes it and every other situation I could think of. 🙂

<?PHP
$a = array(array(1, 2, 3, 4, 5, 6, 7, 8, 9),
array(1, 2, 3, 4, 5,),
array(1, 3, 4, 5, 7),
array(1, 4, 5));

$intersect = array_map("cumulative_intersect", $a);
print_r(cumulative_intersect());

function cumulative_intersect($in = null) {
	static $accumulator = null;
	if (is_null($in)) {
		return($accumulator);
	}
	if (is_null($accumulator)) {
		$accumulator = $in;
	}
	$accumulator = array_intersect($accumulator, $in);
}

?>

[tashbee]

Majik

Thank you so much for taking the time to answer, my delay is due to the fact it gave me loads to do (and I had to upgrade my php).

It's all working, and your help will be at the core of a Taxi routing routine.

Thanks again

Thomas Ashbee