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From: Paul Zimmermann <Paul.Zimmermann@inria.fr>
To: newlib@sourceware.org
Subject: huge powf error
Date: Fri, 11 Dec 2020 06:51:33 +0100	[thread overview]
Message-ID: <mwv9d828m2.fsf@tomate.loria.fr> (raw)

       Hi,

while pursuing my analysis of the accuracy of mathematical libraries [1],
I noticed that Newlib 3.3.0 powf(0x1.ffffeep-1,-0x1.000002p+27) gives +Inf
instead of 0xe.a9a99p+100 which is largely inside the binary32 range. (The
same issue appears with OpenLibm 0.7.0.)

Best regards,
Paul Zimmermann

[1] https://homepages.loria.fr/PZimmermann/papers/#accuracy

             reply	other threads:[~2020-12-11  5:51 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-11  5:51 Paul Zimmermann [this message]
2020-12-11 15:57 ` [PATCH] Fix error in powf for x close to 1 and large y Fabian Schriever
2020-12-11 17:02   ` Paul Zimmermann
2020-12-11 21:02   ` Jeff Johnston

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