How to implode subarrays in a 2-dimensional array?

I want to implode values in to a comma-separated string if they are an array:

I have the following array:

$my_array = [
    "keywords" => "test",
    "locationId" => [ 0 => "1", 1 => "2"],
    "industries" => "1"
];

To achieve this I have the following code:

foreach ($my_array as &$value)
    is_array($value) ? $value = implode(",", $value) : $value;
unset($value);

The above will also change the original array. Is there a more elegant way to create a new array that does the same as the above?

I mean, implode values if they are an array in a single line of code? perhaps array_map()? …but then I would have to create another function.

Answer

Just create a new array and set the elements (-;

<?php
...
$new_array = [];
foreach ($my_array as $key => $value)
     $new_array[$key] = is_array($value) ? implode(",", $value) : $value;