插入空值到小數組

Question

我有以下的數組：

Array 
(
    [xx] => Array 
     (
      [0] => 3 
      [1] => 10 
      [2] => 1 
      [3] => 5 
      [4] => 4 
      [5] => 15 
      [6] => 49 
      [7] => 14 
      [8] => 7 
      [9] => 2 
      [10] => 3 
     ) 

    [yy] => Array 
     (
      [0] => 1 
      [1] => 2 
      [2] => 1 
      [3] => 2 
     ) 

) 

我要插入空值通過與XX陣列進行比較來YY陣列裝置通過用較大的陣列比較我需要插入空值到更小的數組在他們的索引。最後我需要輸出像

Array 
(
    [xx] => Array 
     (
      [0] => 3 
      [1] => 10 
      [2] => 1 
      [3] => 5 
      [4] => 4 
      [5] => 15 
      [6] => 49 
      [7] => 14 
      [8] => 7 
      [9] => 2 
      [10] => 3 
     ) 

    [yy] => Array 
     (
      [0] => 1 
      [1] => 2 
      [2] => 1 
      [3] => 2 
      [4] => null 
      [5] => null 
      [6] => null 
      [7] => null 
      [8] => null 
      [9] => null 
      [10] => null 
     ) 

) 

不僅xx和yy。數組可能會擴展。我們必須比較每個數組，並在較小的數組中插入空值，並與較大數組的大小相匹配。最後每個數組數應相同

Answer 1

假設你想墊的YY陣列XX的大小相同：

$array['yy'] = array_pad($array['yy'], count($array['xx']), null); 

爲了均衡一大堆陣列：

$length = max(array_map('count', $array)); 
$array = array_map(
    function (array $a) use ($length) { return array_pad($a, $length, null); }, 
    $array 
);