Nope, it's not you. There are still some bugs with this code and I'm trying to fix them. You can see the problem if you get random values in a loop and string compare with the fraction until you get an error. The problem with FractionPart is that when you subtract the whole - floor(whole) you don't get the exact fraction, you get an approximation which means sometimes FractionPart will be quite inaccurate. I'm not sure what to do about it yet.