Grouping 2D Array Data Utilizing Column Values to Create a 3D Array

Grouping multidimensional array elements based on a specific column's values can be achieved using a structured approach. Here's a detailed explanation of how to accomplish this task:

Sorting the Data

To group the data, we first need to sort it according to the level key. A temporary array can be utilized for this purpose:

$level_arr = [];
foreach ($input_arr as $key => &$entry) {
    $level_arr[$entry['level']][$key] = $entry;
}

This sorting operation creates an array where each key represents a level value, and the corresponding values are arrays containing the elements with that level.

Building the 3D Array

Once the data is sorted, we can construct the desired 3D array:

$result_arr = [];
foreach ($level_arr as $level => $level_data) {
    foreach ($level_data as $index => $entry) {
        $result_arr[$level][$index] = $entry;
    }
}

The result is a 3D array where each top-level key represents a level, the second-level keys are the original indices, and the values are the associated data elements.

Considerations

• If control over the initial array's construction is possible, structuring it correctly from the start can eliminate the need for sorting and restructuring.
• The naming of array keys and indices may need to be adjusted depending on the specific use case.
• Additional data manipulation may be required based on the desired format of the final 3D array.