Reference for build options

Scipy has several tunable build-time options, which can be set.

  • site.cfg: build-time library configuration file, see site.cfg.example for details.

  • Environment variables NPY_LAPACK_ORDER, NPY_BLAS_ORDER, OPENBLAS, ATLAS, etc., also controlling library configuration. See Numpy documentation for more details.

  • Environment variable NPY_USE_BLAS_ILP64=1: build using 64-bit integer size (ILP64) BLAS+LAPACK libraries.

    Note that even when this is set, Scipy requires also 32-bit integer size (LP64) BLAS+LAPACK libraries to be available and configured. This is because only some components in Scipy make use of the 64-bit capabilities.