Thanks a lot for your explanation. Could you please share your petsc code to test this ?
Thanks, Xiaodong On Fri, Jun 7, 2024 at 10:12 PM Barry Smith <bsm...@petsc.dev> wrote: > > If I run with -pc_type lu it solves the system > > If I run with the default (ILU) -ksp_monitor_true_residual > -ksp_converged_reason it does not converge. In fact, it makes no real > progress to the solution. > > It is always important to use KSPGetConvergedReason() or > -ksp_converged_reason or -ksp_error_if_not_converged to check that the > solver has actually converged. > > If I run with -ksp_gmres_restart 100 it converges in 75 iterations. > > Barry > > > > > On Jun 7, 2024, at 8:03 PM, neil liu <liufi...@gmail.com> wrote: > > This Message Is From an External Sender > This message came from outside your organization. > Dear Petsc developers, > > I am using Petsc to solve a complex system ,AX=B. > > A is complex and B is real. > > And the petsc was configured with > Configure options --download-mpich --download-fblaslapack=1 --with-cc=gcc > --with-cxx=g++ --with-fc=gfortran --download-triangle > --with-scalar-type=complex > > A and B were also imported to matlab and the same system was solved. > The direct and iterative solver in matlab give the same result, which are > quite different from the result from Petsc. > A and B are attached. x from petsc is also attached. I am using only one > processor. > > It is weird. > > Thanks a lot. > > Xiaodong > <A.m><xPetsc.m><B.m> > > >
