php - 如何对多维数组求和

Question

I have data below :

Array(
        [A] => Array
            (
                [AA] => 10
            )

        [B] => Array
            (
                [BA] => 5
                [BB] => 1
                [BC] => -2
            )

        [C] => Array
            (
                [CA] => 3
                [CB] => 0
            )
    )

I want to sum the value of second element my array (BA,BB,BC, etc) like this :

    Array(
        [A] => 10        
        [B] => 4
        [C] => 3
    )

I've tried to do with foreach (I'm using php as my platform) but the result is wrong, can someone give me explanation and the logic to solve this? thanks

Answer 1

You can loop thru your array and use array_sum

$arr = array(
    "A" => array
        (
            "AA" => 10,
        ),

    "B" => array
        (
            "BA" => 5,
            "BB" => 1,
            "BC" => -2
        ),

    "C" => array
        (
            "CA" => 3,
            "CB" => 0
        )
);

$result = array();
foreach( $arr as $key => $val ){
    $result[$key] = array_sum ( $val );
}

echo "<pre>";
print_r( $result );
echo "</pre>";

This will result to:

Array
(
    [A] => 10
    [B] => 4
    [C] => 3
)

Doc: http://php.net/manual/en/function.array-sum.php