Get intersecting values per row of a 2d array where found in another flat array

Question

I have an array

[
    [0 => 20, 1 => 36, 3 => 42],
    [0 => 21, 1 => 42, 2 => 30],
]

And I have a second array of

[24, 42, 26, 12] 

I want to use array_intersect() to get the values that are the same from each array. What I am having trouble with is figuring out how to properly set up the code to do that. I would hope to have this

[
    [42],
    [42],
]

Answer 1

To match your example output, you can simply use a foreach loop. In your example, the 2D array is $array1 and the 1D array is $array2.

$output = [];

foreach ($array1 as $array) {
    $output[] = array_intersect($array, $array2);
}

Note that declaring an array with [] is only supported in PHP versions >= 5.4. For PHP versions < 5.4:

$array1 = array(array(20, 36, 42), array(21, 42, 30));
$array2 = array(24, 42, 26, 12);

$output = array();

foreach ($array1 as $array) {
    $output[] = array_intersect($array, $array2);
}