Fortran 90 modules by Ernst Meese for the compressed sparse row (CSR) and the modified sparse row (MSR) data storage formats, a very general incomplete LU factorisation routine, the Krylov subspace solvers CGS, BiCGSTAB and GMRES.
The optimqr program will read a description of the sparsity pattern of some system matrix for system of linear equations. It will then apply heuristic branch and bound search to find a near-optimal ordering of the rows and columns of the system matrix...