Ben,
This stuff has worked unchanged since the 1990s when we had a _really_ far sighted fellow in Debian come up with the 'switch the links' scheme which was (and is) subsequently deployed by many numerical applications within Debian, R and e.g. Octave included. And I used this ability to switch over a decade ago in a never-quite-finished paper which resulted in a package as well as a vignette as paper draft on CRAN: gcbd [1] It used the ability to switch between implementation to time and compare and benchmark the various BLAS and LAPACK libraries -- which was then motivated by a comparison with GPUs. (The actual code / package is stale-ish as some of the underlying packages have gone as eg the GPU one -- but the mechanics you are after still work the exact same way on Debian and derivarives including Ubuntu and PopOS.) (As a complete aside, the state of the art here is now one level up in libraries based on flame/blis (a riff on blas) which can do a similar logical switch _at runtime_ (rather than by flipping softlinks and restarting the app). Julia and some other languages uses that, I think Fedora may have it in its R build as well. Inaki may know more...) That said, from the top of my head, I think you error may just be with the second R compilation -- I always (i.e. for the Debian package) use both --with-blas --with-lapack and not just --with-blas. And I do there is public: if you know where to look you can see the exact invocation of the Debian build of the R package (which Ubuntu and Pop and ... then shadow) [2] Hth, Dirk [1] https://cran.r-project.org/package=gcbd [2] https://sources.debian.org/src/r-base/4.0.4-1/debian/rules/ (and I apologise for how messy this still is) -- https://dirk.eddelbuettel.com | @eddelbuettel | e...@debian.org ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
