在php中交换（twist）多维数组

Question

i want to "twist" a 2d array by "90°"..

let me explain that.

I have an array like this:

array(
    array( adam , brad , chris , david ),
    array( 21   , 23   , 22    , 26    )
)

and i want to convert that into something like this:

array(
    array( adam  , 21 ),
    array( brad  , 23 ),
    array( chris , 22 ),
    array( david , 26 )
)

how can i do that ?

Answer 1

Though I'd throw a foreach out there:

$array = array(
    array('adam', 'brad', 'chris', 'david'),
    array(21, 23, 22, 26)
);

$final_array = array();
foreach ($array[0] as $k => $v)
{
    $final_array[] = array($array[0][$k], $array[1][$k]);
}

print_r($final_array);

After some confusion in the comments to this it has been pointed out that you can shrink the code to this:

foreach ($array[0] as $k => $v)
{
    $final_array[] = array($v, $array[1][$k]);
}

Thanks Stan

Answer 2

Something like this should work:

// Your array stored as $arr

$newArr = array();
for ($i = 0;$i < count($arr[0]); $i++) {
    $newArr[] = array($arr[0][$i],$arr[1][$i]);
}

EDIT: You tag sorting, but the array is already sorted, do you want sorting too?

Answer 3

Here's one for associative arrays (which are a kind of 2d array):

// Take array like ([0] => ('key1' => 'value1', 'key2' => 'value2'), [1] => ('key1' => 'value45', 'key2' => 'value3'))
// and transform it to like ('key1' => ([0] => 'value1', [1] => 'value45'), 'key2' => ([0] => 'value2', [1] => 'value3'))
function array_twist(array $array) {
    $number_of_rows = count($array);
    $twisted_array = array();
    for ($i = 0; $i < $number_of_rows; ++$i) {
        $fields = array_keys($array[$i]);
        foreach ($fields as $field) {
            $data = $array[$i][$field];
            if ($data != '') {
                $twisted_array[$field][] = $data;
            }
         }
     }
   return $twisted_array;
}