* error in tgamma
@ 2023-02-08 15:55 Paul Zimmermann
2023-02-08 16:09 ` error in tgammaf Paul Zimmermann
0 siblings, 1 reply; 2+ messages in thread
From: Paul Zimmermann @ 2023-02-08 15:55 UTC (permalink / raw)
To: newlib; +Cc: vincenzo.innocente
Hi,
while testing Newlib 4.3.0, I also noticed the following regression
with respect to 4.2.0 for tgammaf:
zimmerma@tartine:~/svn/tbd/20/src/binary32_exhaustive$ VERBOSE=-v ./doit2.newlib tgamma
Checking tgamma with newlib-4.3.0.20230120
Using RedHat newlib
MPFR library: 4.2.0
MPFR header: 4.2.0 (based on 4.2.0)
Checking function tgammaf with MPFR_RNDN
...
libm wrong by up to nan ulp(s) [9223372036854775808] for x=-0x1p+0
tgamma gives inf
mpfr_tgamma gives -nan
For a negative integer, tgamma should return NaN.
Best regards,
Paul Zimmermann
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: error in tgammaf
2023-02-08 15:55 error in tgamma Paul Zimmermann
@ 2023-02-08 16:09 ` Paul Zimmermann
0 siblings, 0 replies; 2+ messages in thread
From: Paul Zimmermann @ 2023-02-08 16:09 UTC (permalink / raw)
To: Paul Zimmermann; +Cc: newlib, vincenzo.innocente
sorry I fixed the subject which was misleading.
This is for tgammaf (and not tgamma), i.e.,
the single precision function.
Paul
> Date: Wed, 08 Feb 2023 16:55:51 +0100
> From: Paul Zimmermann <Paul.Zimmermann@inria.fr>
> CC: vincenzo.innocente@cern.ch
>
> Hi,
>
> while testing Newlib 4.3.0, I also noticed the following regression
> with respect to 4.2.0 for tgammaf:
>
> zimmerma@tartine:~/svn/tbd/20/src/binary32_exhaustive$ VERBOSE=-v ./doit2.newlib tgamma
> Checking tgamma with newlib-4.3.0.20230120
> Using RedHat newlib
> MPFR library: 4.2.0
> MPFR header: 4.2.0 (based on 4.2.0)
> Checking function tgammaf with MPFR_RNDN
> ...
> libm wrong by up to nan ulp(s) [9223372036854775808] for x=-0x1p+0
> tgamma gives inf
> mpfr_tgamma gives -nan
>
> For a negative integer, tgamma should return NaN.
>
> Best regards,
> Paul Zimmermann
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2023-02-08 16:09 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-02-08 15:55 error in tgamma Paul Zimmermann
2023-02-08 16:09 ` error in tgammaf Paul Zimmermann
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).