qrupdate is a Fortran library for fast updates of QR and Cholesky
decompositions.

This requires a BLAS/LAPACK implementation. Choose one of these package
sets:

 * OpenBLAS (includes both a BLAS and a LAPACK implementation)
 * atlas (includes both a BLAS and a LAPACK implementation)
 * blas, lapack (the Netlib reference implementations)

If more than one set is installed (assuming there are no packaging
conflicts) then the auto-detection will use the first implementation
from this list that it finds. If in doubt, choose the Netlib reference
implementations; other packages that require a BLAS or LAPACK
implementation may not build if they are not configured to detect/use
alternate implementations.