> Damn, this was the bit I meant to comment upon - hard and fast rules
> are dangerous. Integral types are distinctly different to floating
> point types, and you should be aware of which one you are using and
> why. You definitely should not be using floats when you require
> integral mathematics, or reliable accounting since 1.0 is only an
> approximation to 1.
>
> Cheers
>
> Tom
>
> >>> 1.0 * 10000000000000000000000000000
>
> 9.9999999999999996e+27
Actually, 1.0 is NOT an approximation to 1. It is precisely 1. All
integral values up to 2^53-1 can be represented exactly. So can many
rational fractions (roughly, those in which the denominator is a power
of two and the numerator and denominator don't differ by a really big
ratio).
The reason the above example fails isn't the 1.0, it's because the
second number (10^28) is bigger than 2^53, so IT can't be represented
exactly.
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