On Thu, Oct 22, 2020 at 3:13 PM baikadi pranay <[email protected]> wrote:
> Hello, > > I am trying to find the condition number of the A matrix for a linear > system I am solving. I have used the following commands. > > *./a.out -ksp_monitor_singular_value -ksp_type gmres -ksp_gmres_restart > 1000 -pc_type none*However, the execution comes to a halt after a few > iterations with the following error. > [0]PETSC ERROR: > ------------------------------------------------------------------------ > [0]PETSC ERROR: Caught signal number 8 FPE: Floating Point > Exception,probably divide by zero > [0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger > [0]PETSC ERROR: or see > http://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind > [0]PETSC ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS > X to find memory corruption errors > [0]PETSC ERROR: likely location of problem given in stack below > [0]PETSC ERROR: --------------------- Stack Frames > ------------------------------------ > [0]PETSC ERROR: Note: The EXACT line numbers in the stack are not > available, > [0]PETSC ERROR: INSTEAD the line number of the start of the function > [0]PETSC ERROR: is given. > [0]PETSC ERROR: [0] LAPACKgesvd line 40 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/impls/gmres/gmreig.c > [0]PETSC ERROR: [0] KSPComputeExtremeSingularValues_GMRES line 22 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/impls/gmres/gmreig.c > [0]PETSC ERROR: [0] KSPComputeExtremeSingularValues line 59 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/interface/itfunc.c > [0]PETSC ERROR: [0] KSPMonitorSingularValue line 130 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/interface/iterativ.c > [0]PETSC ERROR: [0] KSPMonitor line 1765 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/interface/itfunc.c > [0]PETSC ERROR: [0] KSPGMRESCycle line 122 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/impls/gmres/gmres.c > [0]PETSC ERROR: [0] KSPSolve_GMRES line 225 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/impls/gmres/gmres.c > [0]PETSC ERROR: [0] KSPSolve line 678 > /packages/7x/petsc/3.11.1/petsc-3.11.1/src/ksp/ksp/interface/itfunc.c > [0]PETSC ERROR: --------------------- Error Message > -------------------------------------------------------------- > [0]PETSC ERROR: Signal received > [0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html > for trouble shooting. > [0]PETSC ERROR: Petsc Release Version 3.11.1, Apr, 12, 2019 > [0]PETSC ERROR: ./a.out on a linux-gnu-c-debug named > cg17-9.agave.rc.asu.edu by pbaikadi Thu Oct 22 12:07:11 2020 > [0]PETSC ERROR: Configure options > [0]PETSC ERROR: #1 User provided function() line 0 in unknown file > -------------------------------------------------------------------------- > MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD > with errorcode 59. > > NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes. > You may or may not see output from other processes, depending on > exactly when Open MPI kills them. > -------------------------------------------------------------------------- > Is the error because the A matrix is singular (causing the max/min to be > undefined)? Please let me know. > No. It is more likely that there is an invalid value, like an Inf or NaN. Thanks, Matt > Thank you, > Sincerely, > Pranay. > ᐧ > -- 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 https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>
