PHP: Remove parent array and merge the lower arrays into one array
Example of array
$arr = [ [0] => Array ( [attribute_color] => blue ) [1] => Array ( [attribute_width] => 100 ) ]
to:
Array ( [attribute_color] => blue [attribute_width] => 100 )
Here you can use this short PHP function. It works as soon as the upper array is number-indexed, as in the example shown.
$flat = call_user_func_array('array_merge', $arr);