Fork of NITSOL project by H.F.Walker: Taken from here

Changes:

• classical modified Gram-Schmidt GMRES is implemented to complement simpler GMRES
• finite-difference precision can be specified to handle RHS which is evaluated with lower accuracy
• common blocks are eliminated, all inputs and outputs are passed as parameters
• example to test Krylov solvers is added
• pieces of BLAS and LAPACK removed, user should link to external BLAS and LAPACK
• example CMake build file is provided