On Tue, Aug 30, 2016 at 7:01 AM, Florian Lindner <[email protected]> wrote:
> Hello, > > there is a FAQ and a Stackoverflow article about getting the condition > number of a petsc matrix: > > http://www.mcs.anl.gov/petsc/documentation/faq.html#conditionnumber > http://scicomp.stackexchange.com/questions/34/how-can-i- > estimate-the-condition-number-of-a-large-sparse-matrix-using-petsc > > Both tell me to add: > > -pc_type none -ksp_type gmres -ksp_monitor_singular_value > -ksp_gmres_restart 1000 > > to my options. > > I add the line to .petscrc but nothing happens, no additional output at > all. I added -ksp_view, so my .petscrc looks > like that: > Each option must be on its own line .petscrc Thanks, Matt > -ksp_view > -pc_type none -ksp_type gmres -ksp_monitor_singular_value > -ksp_gmres_restart 1000 > > The complete output is below, but something I wonder about: > > GMRES: restart=30, shouldn't that be 1000 > > And where can I read out the condition number approximation? > > Thanks, > Florian > > > KSP Object: 1 MPI processes > type: gmres > GMRES: restart=30, using Classical (unmodified) Gram-Schmidt > Orthogonalization with no iterative refinement > GMRES: happy breakdown tolerance 1e-30 > maximum iterations=10000 > tolerances: relative=1e-09, absolute=1e-50, divergence=10000. > left preconditioning > using nonzero initial guess > using PRECONDITIONED norm type for convergence test > PC Object: 1 MPI processes > type: none > linear system matrix = precond matrix: > Mat Object: C 1 MPI processes > type: seqsbaij > rows=14403, cols=14403 > total: nonzeros=1044787, allocated nonzeros=1123449 > total number of mallocs used during MatSetValues calls =72016 > block size is 1 > (0) 13:58:35 [precice::impl::SolverInterfaceImpl]:395 in initialize: it 1 > of 1 | dt# 1 | t 0 of 1 | dt 1 | max dt 1 | > ongoing yes | dt complete no | > (0) 13:58:35 [precice::impl::SolverInterfaceImpl]:446 in advance: > Iteration #1 > KSP Object: 1 MPI processes > type: gmres > GMRES: restart=30, using Classical (unmodified) Gram-Schmidt > Orthogonalization with no iterative refinement > GMRES: happy breakdown tolerance 1e-30 > maximum iterations=10000 > tolerances: relative=1e-09, absolute=1e-50, divergence=10000. > left preconditioning > using nonzero initial guess > using PRECONDITIONED norm type for convergence test > PC Object: 1 MPI processes > type: none > linear system matrix = precond matrix: > Mat Object: C 1 MPI processes > type: seqsbaij > rows=14403, cols=14403 > total: nonzeros=1044787, allocated nonzeros=1123449 > total number of mallocs used during MatSetValues calls =72016 > block size is 1 > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener
