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From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.theory
Subject: Re: Negative zero doesn't exist
Date: Fri, 30 May 2025 11:16:52 +0300
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On 2025-05-29 22:02:42 +0000, Mr Flibble said:

> Negative zero doesn't exist (in mathematics) so it was a mistake to give
> it a representation in IEEE 754: zero should have a single representation.

That is true in the sense that there is only one zero in a number system
and that zero is nither negative nor positive.

However, when working with approximate values it may be useful to know
whether the true value is positive or negative even when for other values
a little more or less is insignifcant. One such case is temperature where
the difference between -0.1 °C can be significantly different from +0.1 °C
for practical purpoises even when the difference between, say, 5 °C and
6 °C isn't.

-- 
Mikko