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Re: More on trits & tetrits... (long)



On 2010-04-28 12:01:43 -0400, Michel Hack wrote:
> That would be a very different arithmetic.  Yes, 1788 is defined over
> the Reals, but 754 is defined over the Affine Extended Reals, which is
> also why it has signed zeros as well as signed infinities.

From a rigorous mathematical point of view, it isn't: there are no
signed zeros in the affinely extended reals.

http://mathworld.wolfram.com/AffinelyExtendedRealNumbers.html

If x is zero, one has f(-x) = f(x) in the affinely extended reals, but
in IEEE 754 arithmetic, this is wrong, even if all the operations are
exact.

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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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