将数组映射到新数组

Question

I have an array which has an array within it, and I want to create a new array for each of the array values of 'power'. What is the best way to do this?

Original array:

Array
(
    [0] => Array
        (
            [date] => 2019-09-16 15:16:03
            [stid] => 64
            [beam] => 1
            [power] => {1,3,7,8,9}
            [gates] => 5
)

   [1] => Array
        (
            [date] => 2019-09-16 15:17:03
            [stid] => 64
            [beam] => 1
            [power] => {14,15,16}
            [gates] => 3
)
)

Edit: Output array should increment gate started from 1

Array
(
    [0] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 1
            [power] => 1
        )

   [1] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 2
            [power] => 3
         )

   [2] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 3
            [power] => 7
         )

   [3] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 4
            [power] => 8
         )


   [4] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 5
            [power] => 9
         )

   [5] => Array
        (
            [date] => 2019-09-16 15:17:03
            [gate] => 1
            [power] => 14
         )

   [6] => Array
        (
            [date] => 2019-09-16 15:17:03
            [gate] => 2
            [power] => 15
         )

   [7] => Array
        (
            [date] => 2019-09-16 15:17:03
            [gate] => 3
            [power] => 16
         )
)

Continued for all 8 (5 and 3) power values, such that the resultant array is an array of 8 arrays.

Answer 1

# Original Data Structure
$arr = 
[
    [
        'date' => '2019-09-16 15:16:03',
        'stid' => 64,
        'beam' => 1,
        'power' => '{1,3,7,8,9}',
        'gates' => 5
    ],
    [
        'date' => '2019-09-16 15:17:03',
        'stid' => 64,
        'beam' => 1,
        'power' => '{14,15,16}',
        'gates' => 3
    ]
];

$output = [];
foreach ($arr as $a)
{
    $gateCount = 0;
    foreach (explode(',', trim($a['power'], '{}')) as $p) 
    {
        $output[] = [
            'date' => $a['date'],
            'gate' => $gateCount++ % $a['gates'] + 1,
            'power' => $p
        ];
    }
}
print_r($output);

Output:

Array
(
    [0] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 1
            [power] => 1
        )

    [1] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 2
            [power] => 3
        )

    [2] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 3
            [power] => 7
        )

    [3] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 4
            [power] => 8
        )

    [4] => Array
        (
            [date] => 2019-09-16 15:16:03
            [gate] => 5
            [power] => 9
        )

    [5] => Array
        (
            [date] => 2019-09-16 15:17:03
            [gate] => 1
            [power] => 14
        )

    [6] => Array
        (
            [date] => 2019-09-16 15:17:03
            [gate] => 2
            [power] => 15
        )

    [7] => Array
        (
            [date] => 2019-09-16 15:17:03
            [gate] => 3
            [power] => 16
        )

)

Note:

['beam'] and ['stid'] have been left off as per your sample. Can easily be added if you need them.

Answer 2

You can do this:

$newArray = [];
foreach ($oldArray as $element) {
   foreach ($element['power'] as $power) {
      $element['power'] = $power;
      $newArray[] = $element;
   }
}