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Re: Negative zeros?
From: |
Vic Norton |
Subject: |
Re: Negative zeros? |
Date: |
Tue, 13 Sep 2005 20:17:07 -0400 |
At 10:06 PM -0400 9/12/05, John W. Eaton wrote:
For more info, take a look at the section on signed zeros in the paper
What Every Computer Scientist Should Know About Floating-Point
Arithmetic (google the title and you will find it on the web).
At 6:05 AM +0200 9/13/05, David Bateman wrote:
Maybe you should do a google search for the article "Much ado about
zeros sign bit" and read about the importance of having two
representations of zero.
At 9:18 AM +0200 9/13/05, Stefan van der Walt wrote:
The article John referred to is available at
http://eins2002.info.uni-karlsruhe.de/literatur/goldberg-floating-point.pdf
The other one that David referred to was written by William Kahan
(sometimes called father of floating-point mathematics, being the
primary architect of the IEEE standard), but isn't available for free
on the web. Here is a complete reference:
"Branch Cuts for Complex Elementary Functions, or Much Ado About
Nothing's Sign Bit" by William Kahan in "The State of the Art in
Numerical Analysis", (eds. Iserles and Powell), Clarendon Press,
Oxford, 1987.
However, he has many other interesting writings pertaining to
Floating-Point on his webpage at
http://www.cs.berkeley.edu/~wkahan/
(like "Matlab's Loss is Nobody's Gain" and "How Java's Floating-Point
hurts Everyone Everywhere").
I am sorry, John, David, and Stephan. I am a mathematician. I don't
choose to read nonsense. Zero is zero is zero.
I realize that e-1000000 is positive and -e-1000000 is negative and
that these might be represented by 0 and -0 respectively on a
machine. But I will never accept that
0 * (-1) = -0.
Regards,
Vic
--
*---* mailto:address@hidden
| Victor Thane Norton, Jr.
| Mathematician and Motorcyclist
| Bowling Green, Ohio
*---* http://vic.norton.name
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- Negative zeros?, Vic Norton, 2005/09/12
- Re: Negative zeros?, David Bateman, 2005/09/13
- Re: Negative zeros?, Stefan van der Walt, 2005/09/13
- Re: Negative zeros?,
Vic Norton <=
- Re: Negative zeros?, Paul Kienzle, 2005/09/13
- Re: Negative zeros?, Stefan van der Walt, 2005/09/14
- Re: Negative zeros?, Przemek Klosowski, 2005/09/14
- Re: Negative zeros?, Vic Norton, 2005/09/14
- Re: Negative zeros?, Bill Denney, 2005/09/14