Re: accuracy of mathematical functions

[Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>]

On 2021-02-05 03:43, Paul Zimmermann wrote:
> I have updated my comparison with the newly released 2.33 version.
> No big difference with the previous version, except that I included
> the "long double" format (aka ldbl-96), which is not supported by Newlib.
> 
> https://members.loria.fr/PZimmermann/papers/#accuracy

Thanks for doing this work and making it available is greatly appreciated.

While newlib is mainly targeted to smaller platforms, the Cygwin port math 
library supports gcc __FLT64X_...__/__FLT128_...__ under
.../newlib-cygwin/winsup/cygwin/math/ and related includes.

As you may already be aware, clang and gcc have added support for ARM 
__FLT16/__fp16, AMD and Intel have added it to x86/amd64 as CVT16/FP16C 
https://en.wikipedia.org/wiki/F16C, and more compiler and library support are 
likely to follow, as they are already used in graphics and GPGPU areas.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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[Data in binary units and prefixes, physical quantities in SI.]

[Shame your CORE-Math proposal was rejected: desperately needed these days, as 
I've never been a math natural but often seemed more comfortable than other 
programmers doing related work.
Maybe have to comb the literature on reproducible builds, need for verification 
no backdoors or vulnerabilities have been introduced, and testing results 
produced are identical across platforms; maybe comb Risks or contact PGN for 
math horror stories as references and justifications for resubmission.]