php - finding keys in an array that match a pattern

Question

I have an array that looks like:

 Array ( [2.5] => ABDE [4.8] => Some other value ) 

How would I find any key/value pair where the k

Answer 1

To get just the part of the array with matching keys you could also write

$matching_array = array_flip(preg_grep($pattern, array_flip($your_array)));

This might just lead to problems performance-wise, if your array gets too big.