Thank you very much!
Daye At 2019-07-10 02:36:55, "Smith, Barry F." <[email protected]> wrote: > > Most preconditioners don't care if the matrix has non-symmetric non-zero > structure. GAMG requires it have a symmetric nonzero structure. It lists some > options you can try to make it symmetric. > > >> [2]PETSC ERROR: Have un-symmetric graph (apparently). Use >> '-(null)pc_gamg_sym_graph true' to symetrize the graph or >> '-(null)pc_gamg_threshold -1' if the matrix is structurally symmetric. > > > >> On Jul 9, 2019, at 8:30 AM, 我 via petsc-users <[email protected]> >> wrote: >> >> Hello all, >> I set PCGAMG and KSPGRMES to solve the matrix which is formed by a particle >> method such as SPH. But when there is always a PETSC ERROR: >> [2]PETSC ERROR: --------------------- Error Message >> -------------------------------------------------------------- >> [2]PETSC ERROR: Petsc has generated inconsistent data >> [2]PETSC ERROR: Have un-symmetric graph (apparently). Use >> '-(null)pc_gamg_sym_graph true' to symetrize the graph or >> '-(null)pc_gamg_threshold -1' if the matrix is structurally symmetric. >> [2]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html for >> trouble shooting. >> [2]PETSC ERROR: Petsc Release Version 3.9.1, Apr, 29, 2018 >> [2]PETSC ERROR: ./MPS on a arch-linux2-cxx-debug named >> daye-Precision-7920-Tower by daye Tue Jul 9 20:59:39 2019 >> [2]PETSC ERROR: Configure options --with-cc=gcc --with-cxx=g++ >> --with-fc=gfortran --download-mpich --download-fblaslapack --download-hypre >> --with-clanguage=cxx >> [2]PETSC ERROR: #1 smoothAggs() line 418 in >> /home/daye/PETSC/petsc-3.9.1/src/ksp/pc/impls/gamg/agg.c >> [2]PETSC ERROR: #2 PCGAMGCoarsen_AGG() line 970 in >> /home/daye/PETSC/petsc-3.9.1/src/ksp/pc/impls/gamg/agg.c >> [2]PETSC ERROR: #3 PCSetUp_GAMG() line 518 in >> /home/daye/PETSC/petsc-3.9.1/src/ksp/pc/impls/gamg/gamg.c >> [2]PETSC ERROR: #4 PCSetUp() line 923 in >> /home/daye/PETSC/petsc-3.9.1/src/ksp/pc/interface/precon.c >> [2]PETSC ERROR: #5 KSPSetUp() line 381 in >> /home/daye/PETSC/petsc-3.9.1/src/ksp/ksp/interface/itfunc.c >> [2]PETSC ERROR: #6 KSPSolve() line 612 in >> /home/daye/PETSC/petsc-3.9.1/src/ksp/ksp/interface/itfunc.c >> ^C[mpiexec@daye-Precision-7920-Tower] Sending Ctrl-C to processes as >> requested >> [mpiexec@daye-Precision-7920-Tower] Press Ctrl-C again to force abort >> >> This matrix can be solved when I use PCHYPRE and KSPGRMES. But when I change >> the pre-condition to PCGAMG, this error always occurs. Any suggestions about >> that? >> Thank you at first! >> >> Daye >> >> >> >
