qr_mumps is a software package for the solution of sparse,
linear systems on multicore computers.
It implements a direct solution method based on the QR
factorization of the input matrix. Therefore, it is suited
to solving sparse least-squares problems and to computing
the minimum-norm solution of sparse, underdetermined problems.
It can obviously be used for solving square problems in which
case the stability provided by the use of orthogonal transformations
comes at the cost of a higher operation count with respect to solvers
based on, e.g., the LU factorization.
qr_mumps supports real and complex, single or double precision arithmetic.