[Rd] About FlexiBLAS in the R-admin docs

[George Ostrouchov]

I agree that the "R Installation and Administration" guide statement about FlexiBLAS needs an update. Standard R in CentOS Stream 9, which is now downstream from Fedora, gives the following result for Matrix products in sessionInfo():

> sessionInfo()
R version 4.3.1 (2023-06-16)
Platform: x86_64-redhat-linux-gnu (64-bit)
Running under: CentOS Stream 9

Matrix products: default
BLAS/LAPACK: FlexiBLAS OPENBLAS-OPENMP;  LAPACK version 3.9.0
…

So OpenBLAS compiled with OpenMP is the default. FlexiBLAS (via the flexiblas package) is my favorite way to manage core use in multithreaded BLAS computations. It is also the default in the EasyBuild foss compiler toolchain for HPC clusters: https://docs.easybuild.io/common-toolchains/ 

What would be a good way to suggest or construct an update?

Best regards,
George


> Date: Wed, 27 Sep 2023 15:14:43 +0200
> From: =?UTF-8?Q?I=C3=B1aki_Ucar?= <iucar using fedoraproject.org>
> To: "r-devel using r-project.org" <R-devel using r-project.org>
> Subject: [Rd] About FlexiBLAS in the R-admin docs
> Message-ID:
> 	<CALEXWq2x9gygnxt6S906BkQHd139CP783bTDQC4wmeM-uKuW3g using mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
> 
> Hi,
> 
> Not sure if this is the right place for this. The "R Installation and
> Administration" guide states:
> 
>> Apparently undocumented: FlexiBLAS on Fedora provides a complete LAPACK, but not the enhanced routines from ATLAS or OpenBLAS.
> 
> I'm not sure what this means. FlexiBLAS does provide 100% of BLAS and
> LAPACK, and if the active backend (say, OpenBLAS) implements an
> enhanced LAPACK routine, then the call is redirected to the backend.
> If the user switches to another backend and that routine is not
> available there, then the original LAPACK routine is dispatched
> instead.
> 
> Best,
> -- 
> Iñaki Úcar
> 


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