Previous power of 2

Question

There is a lot of information on how to find the next power of 2 of a given value (see refs) but I cannot find any to get the previous power of two.

The only way I f

Answer 1

If you can get the next-higher power of 2, the next-lower power of 2 is either that next-higher or half that. It depends on what you consider to be the "next higher" for any power of 2 (and what you consider to be the next-lower power of 2).