Looking for array's function name?

Question

I have a n-values array:

$input = array( object_a, object_b, object_c, ..., object_n );</code>

I try to find the name of the function which produces this output:

$output = array(
    array( object_a ), array( object_b ), ..., array( object_n ),
    array( object_a, object_b ), array( object_a, object_c ), ..., array( object_a, object_n ),
    array( object_b, object_c ), ..., array( object_b, object_n ),
    ...
    array( object_a, object_b, object_c), ..., array( object_a, object_b, object_n),
    ...
    array( object_a, object_b, object_c, ..., object_n)
);

It looks like cartesian product, but it was not.

I try to program this function, and I successfully create this following part of my results, but I am stuck with 'middle' distribution:

$output = array(
   array( object_a ), array( object_b ), ..., array( object_n ),
   array( object_a, object_b, object_c, ..., object_n)
);

I think middle part can be produce with function recursive call, but I have no clues on how to do it.

Thank you

Here is the beginning of my function:

/**
 *
 * @param array $array this input array
 * example:
 *     $array = array(
 *         A, B, C
 *     );
 *
 * @return array the result array
 * example:
 *     $result = array(
 *         array( A ),          ok
 *         array( B ),          ok
 *         array( C ),          ok
 *         array( A, B ),
 *         array( A, C ),
 *         array( B, C ),
 *         array( A, B, C )     ok
 *     )
 */
private function distribute($array)
{
    $result = array();

    if (is_array($array)) {
        // add array( 'A', 'B', 'C' ) to result
        $result[] = $array;

        if (count($array)>1) {
            // add array( 'A' ), array( 'B' ), array( 'C' ) to result
            foreach ($array as $value) {
                $result[] = array($value);
            }

            // help me to complete this function
        }
    }

    return $result;
}

Answer 1

Comments help me to find function name.

Here is the link to stackoverflow previous answer Finding the subsets of an array in PHP

which refers to php manual http://php.net/manual/en/function.shuffle.php#88408