array_intersect ... dynamic arguments?

[NeutrinaNewt]

I've successfully created comparisons between multiple arrays using array intersect:

$arr_1=array("cat","dog","pig");
$arr_2=array("owl","pig","cat");
$arr_3=array("pig","cat","owl");

$arr_i=array_intersect($arr_1,$arr_2,$arr_3);

print_r($arr_i);
Array ( [0] => cat [2] => pig )

My problem is, I can't always predict how many arrays will need to be "intersected" because users can choose between two and ten different lists to compare.

I've tried for hours to come up with a solution that uses VARIABLE VARIABLES for array names, but array_intersect doesn't seem to be able to take those kind of references.

Anyone else ever have this problem, and (hopefully) solve it?

Thanks if you can help.

NN😕

[Clio]

Hi,
I'm having the same problem. Could you solve it finally?
If so, please show me how you worked it around.

Thanks!

Ana

[Weedpacket]

You'd probably find it easier to store the arrays in an array, e.g.:

$arr[0]=array("cat","dog","pig");
$arr[1]=array("owl","pig","cat");
$arr[2]=array("pig","cat","owl"); 

Then you can loop over the array, noting that

array_intersect($a1, $a2, $a3, $a4, ...)

is equivalent to

array_intersect($a1,
    array_intersect($a2,
        array_intersect($a3,
            array_intersect($a4, ....))))

which is easily done in a loop a la $ai = array_intersect($ai, $a[$i]);

[Clio]

Thanks a lot for the tip!!

Ana