如何从多个其他数组生成具有特定结构的PHP数组

Question

I am trying to generate an array with a specific structure using data from other arrays. I've been playing around with this code a lot and can't seem to figure it out.

    ini_set('display_errors', 1);
    ini_set('display_startup_errors', 1);
    error_reporting(E_ALL & ~E_NOTICE);


    $detList = array(
        '0' => array('0' => 'NULL'),
        '1' => array(
            '0' => '1',
            '1' => '2',
            '2' => '3',
            '3' => '4',
        )
    );

    $ydata = [];
    $rawxdata = '["2018-09-30 18:50:58","2018-09-30 18:53:36"]';

    $rawydata = '{"12345678":{"2018-09-30 18:50:58":["1","1","1","1"]},"87654321":{"2018-09-30 18:53:36":["2","2","2","2"]}}';

    $data = json_decode($rawydata);
    $data = json_decode(json_encode($data), true);
    $xData = json_decode($rawxdata);
    $xData = json_decode(json_encode($xData), true);

    echo '<pre>';

    print_r($detList);
    print_r($xData);
    print_r($data);

    $dataKey = [];

    foreach($data as $key => $value){
        array_push($dataKey, $key);
    }


    for($j=0;$j<count($xData);$j++){
        for($k=0;$k<(count($detList[1])*count($data));$k++){
            if(!isset($ydata[$j])){
                $ydata[$j] = array();
            }

            $key = $dataKey[$j];

            array_push($ydata[$j], (isset($data[$key][$xData[$j]][$k]) ? $data[$key][$xData[$j]][$k] : 'NULL'));
        }
    }

    print_r($ydata);

The output of $ydata that I'm trying to achieve is

Array
(
    [0] => Array
        (
            [0] => 1
            [1] => 1
            [2] => 1
            [3] => 1
            [4] => 'NULL'
            [5] => 'NULL'
            [6] => 'NULL'
            [7] => 'NULL'
        )

    [1] => Array
        (
            [0] => 'NULL'
            [1] => 'NULL'
            [2] => 'NULL'
            [3] => 'NULL'
            [4] => 2
            [5] => 2
            [6] => 2
            [7] => 2
        )

)

Right not I'm getting

Array
(
    [0] => Array
        (
            [0] => 1
            [1] => 1
            [2] => 1
            [3] => 1
            [4] => 'NULL'
            [5] => 'NULL'
            [6] => 'NULL'
            [7] => 'NULL'
        )

    [1] => Array
        (
            [0] => 2
            [1] => 2
            [2] => 2
            [3] => 2
            [4] => 'NULL'
            [5] => 'NULL'
            [6] => 'NULL'
            [7] => 'NULL'
        )

)

All the arrays are dynamically generated and maintain the following logic:

Each index of $rawydata will be an array with the same number of indexes as $rawxdata. Each $rawydata[n][n] will be an array with the same number of indexes as $detList[1].

Answer 1

Concentrating on below single line of code:

array_push($ydata[$j], (isset($data[$key][$xData[$j]]) ? $data[$key][$xData[$j]][$j] : 'NULL'));

The value of data[$key][$xData[$j][$j] is same for all iterations of inner loop as both $key and $j are dependent on outer loop which is constant in inner loop.

I believe you need to check your condition isset($data[$key][$xData[$j]]