Date: Wed, 04 Jul 2001 20:30:20 +0300
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: djgpp AT delorie DOT com
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Subject: Re: DJGPP reserves wrong int size
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> From: invalid AT erehwon DOT invalid (Graaagh the Mighty)
> Newsgroups: comp.os.msdos.djgpp
> Date: Wed, 04 Jul 2001 16:51:18 GMT
> 
> On Sat, 30 Jun 2001 16:31:09 +0300, "Eli Zaretskii"
> <eliz AT is DOT elta DOT co DOT il> sat on a tribble, which squeaked:
> 
> >Yes, I understand.  And that precisely is the sign of a numerical bug,
> >in most cases I've seen.
> 
> I would think if the problem was numerical instability of the
> algorithm, the problem would be *more* pronounced when using a *lower*
> precision.

This is true for some numerical computations, but not for all of
them.

> >Numerical computations are tricky.
> 
> These ones aren't. They just add and multiply and subtract and
> compare, and they only compare for exceeding certain (small)
> magnitudes -- they don't depend on an exact comparison with anything,
> ever.

In any decent course in numerical computation, the first lesson
teaches you that you cannot even solve a quadratic equation without
risking numerical pitfalls.