One does not simply calculate the absolute value

Re:One does not simply calculate the absolute value by FabHK on Sunday August 22, 2021 @05:05PM (#28269595)

Haha, was just going to link that. Here's an ELI5, though not that illuminating:

https://hackernoon.com/negative-zero-bbd5fd790af3

But, bottom line, Kahan (not only the father of IEEE 754, but also, with Golub, father of the SVD!) has thought about it a lot, and though he called the signed zero "a pain in the ass", he also said "There really wasn’t a way around that and you were stuck with it."

http://history.siam.org/pdfs2/Kahan_final.pdf

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Re:One does not simply calculate the absolute value by edflsafoiewq on Monday August 23, 2021 @12:31AM (#28272350)

I don't really understand. Why is it important that there be two zeros so that

1/ (+0) = +∞ but 1/ (–0) = –∞

but not that there be two, say, 3s so that

1/ (3⁺ – 3) = +∞ but 1/ (3⁻ – 3) = –∞

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Re:One does not simply calculate the absolute value by pests on Monday August 23, 2021 @03:13AM (#28273057)

But we already have two threes: +3 and -3.

It's not that it's important there be two, just every number already had 2 except for 0.

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