On Thu, Jul 8, 2021 at 11:47 PM Jerry Morrison < jerry.morrison+nu...@gmail.com> wrote:
> > On Wed, Jul 7, 2021 at 10:14 PM Matti Picus <matti.pi...@gmail.com> wrote: > >> >> On 8/7/21 2:23 am, Jerry Morrison wrote: >> > Got it! >> > >> > *Summary:* >> > * Installing a numpy wheel (e.g. `pip install numpy==1.21.0`) uses its >> > embedded OpenBLAS on every platform that has a wheel. >> > That OpenBLAS is always compiled with gcc/gfortran. >> > In this case, `np.show_config()` reports `library_dirs = >> > ['/usr/local/lib']` even though there's no libblas in that directory. >> > >> > * Installing numpy from source (e.g. `pip install numpy==1.21.0 >> > --no-binary numpy)` looks for BLAS & LAPACK libraries at build time as >> > influenced by the environment vars NPY_BLAS_ORDER/NPY_LAPACK_ORDER or >> > by the file ~/.numpy-site.cfg. >> > On macOS, 'accelerate' is in the default search order after >> 'openblas'. >> > On macOS < 11.3, importing numpy that's linked to Accelerate will >> > detect an Accelerate bug and raise a RuntimeError. >> >> >> That seems correct, although admittedly show_config could do a better >> job. The problem is that not every BLAS implementation provides a >> convenient method to self-report. >> > > For implementations that don't self-report, could show_config detect that > it's using embedded OpenBLAS or a system Accelerate library? > It's not about "self reporting". What `show_config` shows for BLAS/LAPACK is the build time configuration, not the one at runtime. The paths are present in `numpy/__config.py__`, which is a file generated by the build process. > > >> >> It might be nice to document all this somewhere more permanent, the >> docstring for show_config might be a good place to start. >> > > Agreed. On the https://numpy.org/install/ installation page? > Do you want a PR? (How to get the translations?) > Thanks, a PR would be nice. It's too detailed for the website; Matti's suggestion was in the docstring of `show_config`, which is defined at https://github.com/numpy/numpy/blob/main/numpy/distutils/misc_util.py#L2332 Cheers, Ralf > _______________________________________________ > NumPy-Discussion mailing list > NumPy-Discussion@python.org > https://mail.python.org/mailman/listinfo/numpy-discussion >
_______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@python.org https://mail.python.org/mailman/listinfo/numpy-discussion
