Selecting every nth item from an array

Question

What would be the most efficient way to select every nth item from a large array? Is there a \'smart\' way to do it or is looping the only way?

Some points to c

Answer 1

If this really is a bottleneck, you might want to consider rethinking your design in order to make it numerically indexed.

EDIT: Or create and maintain a seperate array with just the 205th items (which gets updated at insert or something like that).