daverave:

It doesn't surprise me that it's slower than yours, as I was just trying to make it work first. I'll try to find some time to speed it up a bit. There are several tricks I've been thinking about. First, I'd prune the normalized ranges to remove the redundant ranges. Next, there are cases where you don't have to compute the value for all the entries of @working. Ideally, I'd remove that inner loop.

...roboticus