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From: dl@G.OSWEGO.EDU (Doug Lea)
Newsgroups: gnu.g++.lib.bug
Subject: problems with `tests' &c
Message-ID: <8910201606.AA18287@g.oswego.edu>
Date: 20 Oct 89 16:06:06 GMT
References: <8910201558.AA00758@PROMETHEUS.MIT.EDU>
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>    The Rational tests often come out with numbers that are as much as 32
>    times larger than those in expected.out.
> 
> More precisely: The denominator is some multiple of that in
> expected.out, and the numerator is multiplied by the same factor, with
> some small number added.  The ratio is approximately the same as in
> expected.out, not 32 times larger.


This is probably a machine precision difference. double<->Rational
conversions attempt to use exactly as much precision as is used for
doubles. This leads to odd-looking Rationals, that may be expected
to vary across machines. If you send me your tRational results, I'll
try to double check this.

-Doug