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Re: Nitpick with FLOOR etc.
> From: Aubrey Jaffer <agj@xxxxxxxxxxxx>
> Inverting +/0. or -/0. returns 0.0. So the name "error object"
> wouldn't seem to apply either.
- I still don't understand how it's acceptable for (/ 1/-0.0) => 0.0, as
it seems neither necessary, nor desirable to propagate IEEE-754 mistake.
> | This brings up an important distinction in "infinities;"
> | When you divide by exact zero you get an absolute infinity.
> | (which, perversely, is neither positive nor negative, because
> | exact zero isn't positive or negative.) Call this EO1.
> We have already covered this ground. Division by zero is undefined;
> SRFI-70 extends division by returning infinities in these cases:
> (/ -5. 0) ==> -/0.; (/ 1. 0) ==> +/0., which are consistent with
> the one-sided limits:
> (limit / 0 1.0e-9) ==> +/0.
> (limit / 0 -1.0e-9) ==> -/0.
- however as multiplication by 0 should result in 0, 0/x => 0
regardless of its denominator.
> | When you divide 1 by (say) 5e-323, you get a different kind of
> | EO, which is "results too large to represent" but which
> | is often mistaken for an actual infinity. Call this EO2.
> The result of division by zero was chosen to be the same as the result
> of (/ 1 5e-323). We could split +/0 into any number of regions. One
> was chosen, which happens to be supported by IEEE-754.
- who's model of infinitesimals isn't likely something worthy of mimicking.