Hi everybody, I would like to ask what solution is computed if I try to solve the linear system relative to the problem in subject without creating the null space. I tried with and without the call to MatNullSpaceCreate(m_communicator, PETSC_TRUE, 0, NULL, &nullspace); and I get zero averaged solution with and the same solution plus a constant without. How does PETSc work in the second case? Does it check the matrix singularity? And is it able to create the null space with the constant automatically? Thanks.
Marco Cisternino, PhD [email protected] _______________________________ OPTIMAD Engineering srl Via Giacinto Collegno 18, Torino, Italia. +3901119719782 www.optimad.it
