080104-1644 EST USA
I do not understand this either. How old is your machine?
I do not believe my machines convert 100.5200 into a floating point for storage. It looks like a possible error converting to floating point and then back again. In a system like a CNC machine I would think that data moves, adds, and subtracts would be done in integer arithmetic to avoid cumulative rounding errors. With todays processors and the travel range of machines I would even think multiply and divide would be in integer.
I will try to remember to run the experiment on one of my machines.
Maybe your numbers are too big. Try 30.52 .