I don't understand what you mean by "reverse"... I've seen your patch but didn't help me... Do you want 0 to become 1, 1 to become 0 and 0.5 (the center) to stay the same? [scale 0. 1. 1. 0.] or [- 0.5] followed by [* -1.]

If you mean to reverse the playback of the function graph, you could change it by connecting a toggle to the 2nd inlet of the counter object...

Reversing directions on the counter driving function does what I'd like to do to any random/arbitrary stream of floats-- if descending it would fold back at that point and rise, if ascending then reverse direction and fall. A section going from 0.2 to 0.1 would instead go 0.2 to 0.3. It seems the amount to be added/subtracted from a straight inverted stream is like a sine wave-- 0 at .5 and near + 1 -1 at each end.