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Re: New approach to annex D of the 754-R proposal.
On 2007-06-21 22:34:11 +1000, Peter Henderson wrote:
Signed infinities and signed zeros are inextricably linked to each other.
One is the mirror image of the other. The problems in assigning a sign to
exact infinity are exactly the same as those of assigning a sign to zero.
No, I recall that +0 = -0, but +Inf != -Inf.
Also, the value -0 of sqrt(-0) makes some sense since on the
real numbers, sqrt(0) = 0, but choosing -Inf for a function
f(x) = 1/sqrt(x) on x = -0 doesn't make any sense.
Contrary to the case of 0, the sign on the infinity is not just
additional information. It is really part of the value, and one
has a total order on the numbers:
-Inf < neg reals < 0 (includes -0 and +0) < pos reals < +Inf.
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.org/>
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Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)