I used src/ksp/ksp/tutorials/ex10.c and saved the A and b into a PETSc binary file from Matlab with PetscBinaryWrite() in PETSC_DIR/share/petsc/matlab
> On Jun 7, 2024, at 10:53 PM, neil liu <[email protected]> wrote: > > 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 <[email protected] > <mailto:[email protected]>> 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 <[email protected] >>> <mailto:[email protected]>> 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> >>
