You're right about the first part, of course. But don't you just need to truncate? In any case, my point was more that it's not "piecewise linear". Piecewise l

You're right about the first part, of course. But don't you just need to truncate? In any case, my point was more that it's not "piecewise linear". Piecewise linear means that the map is defined on some interval; it's not, it's defined on a discrete set of values. To take your example, the map isn't defined on e.g., 2.3. You can decide to interpolate linearly between the value at 2.25 and the value at 2.5, but that's a decision you make which isn't reflected in the code. Or said differently: do you consider that any map defined on a discrete subset of R is really a piecewise linear map?