Welcome to the world of floating point arithmetic!

Short version: 0.01 can not be represented exactly as a floating point number, there's a tiny error here. Since you always subtract the same number, this error accumulates to the point where the difference shows up.

Long version: What Every Programmer Should Know About Floating-Point Arithmetic.

In reply to Re: what did I just see..? by haj
in thread what did I just see..? by ishaybas

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