PHP：合并数组并添加键值

Question

我有一个包含数组的多维数组，每个数组都包含一个artisan和closeness键。我想合并多个数组（如果相同）artisans到一个数组，它是从中合并的数组closeness的值的总和。closeness也就是说，这个数组：Array(    [0] => Array        (            [artisan] => carpenter            [closeness] => 0.8        )    [1] => Array        (            [artisan] => brick layer            [closeness] => 0.4        )    [2] => Array        (            [artisan] => electrician            [closeness] => 0.9        )    [3] => Array        (            [artisan] => carpenter            [closeness] => 0.8            [is_real] => 1        )    [4] => Array        (            [artisan] => brick layer            [closeness] => 0.9            [is_real] => 1        ))应该变成：Array(    [0] => Array        (            [artisan] => carpenter            [closeness] => 1.6 //0.8+0.8        )    [1] => Array        (            [artisan] => brick layer            [closeness] => 1.3  //0.4+0.9        )    [2] => Array        (            [artisan] => electrician            [closeness] => 0.9 //remains 0.9 because it is the only array with artisan value of electrician        )

Answer 1

试试这个循环

//create new array to hold values in the format you need

$new_array = [];

//loop through old array

foreach($old_array as $arr) {

    $artisan = $arr['artisan'];

    $closeness = $arr['closeness'];

    //check if `$artisan` key does not exists in `$new_array`

    if(!array_key_exists($artisan, $new_array)) {

        //create key in `$new_array` if it doesn't exist already

        //for this key, create an array containing the values in the format you need

        $new_array[$artisan] = [

            'artisan' => $artisan, 

            'closeness' => $closeness

        ];

    } else {

        //increase closeness in `$new_array` with key `$artisan` if key did already exist

        $new_array[$artisan]['closeness'] += $closeness;

    }

}

//replace keys which contain `$artisan` with sequential numbers, as per your expected output.

//if you don't do this, it will still work, but your array keys will be equal to the artisan type.

$new_array = array_values($new_array);

print_r($new_array);

结果：

Array

(

    [0] => Array

        (

            [artisan] => carpenter

            [closeness] => 1.6

        )

    [1] => Array

        (

            [artisan] => brick layer

            [closeness] => 1.3

        )

    [2] => Array

        (

            [artisan] => electrician

            [closeness] => 0.9

        )

)

如果删除该array_values()行，结果将如下所示：

Array

(

    [carpenter] => Array

        (

            [artisan] => carpenter

            [closeness] => 1.6

        )

    [brick layer] => Array

        (

            [artisan] => brick layer

            [closeness] => 1.3

        )

    [electrician] => Array

        (

            [artisan] => electrician

            [closeness] => 0.9

        )

)

Answer 2

怎么样：

$results = array(); // create results array

foreach( $array as $k => $i ) {

    $found = false;

    foreach ( $results as $k => $r ) {

        if ( $r[ "artisan" ] == $i[ "artisan" ] ) {

            $results[ $k ][ "closeness" ] += $i[ "closeness" ];

            $found = true;

            break;

        }

    }

    if ( ! $found ) array_push( $results, $i );

}