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