Some error when I try to solve a matricial system

Matthew Knepley knepley at
Thu Dec 21 09:25:25 CST 2006

You have a zero pivot in the factorization. This is explained at the
link given in the error message. You could try a different preconditioner.


On 12/21/06, Isabel Gil <misabel at> wrote:
> Hello PETSc's users,
> I have just started to use PETSc and when I try to solve the matricial
> system I obtain the following error sentences:
> [0]PETSC ERROR: MatLUFactorNumeric_SeqAIJ() line 538 in
> src/mat/impls/aij/seq/aijfact.c
> [0]PETSC ERROR: Detected zero pivot in LU factorization
> see
> [0]PETSC ERROR: Zero pivot row 277017 value 2.16144e-10 tolerance 1e-12
> * rs 526.244!
> [0]PETSC ERROR: MatLUFactorNumeric() line 1843 in src/mat/interface/matrix.c
> [0]PETSC ERROR: PCSetUp_ILU() line 854 in src/ksp/pc/impls/ilu/ilu.c
> [0]PETSC ERROR: PCSetUp() line 797 in src/ksp/pc/interface/precon.c
> [0]PETSC ERROR: KSPSetUp() line 232 in src/ksp/ksp/interface/itfunc.c
> [0]PETSC ERROR: PCSetUpOnBlocks_BJacobi_Singleblock() line 747 in
> src/ksp/pc/impls/bjacobi/bjacobi.c
> [0]PETSC ERROR: PCSetUpOnBlocks() line 830 in src/ksp/pc/interface/precon.c
> [0]PETSC ERROR: KSPSetUpOnBlocks() line 156 in
> src/ksp/ksp/interface/itfunc.c
> [0]PETSC ERROR: KSPSolve() line 344 in src/ksp/ksp/interface/itfunc.c
> I would be really grateful if you could say to me where the problem
> could be in order to sort it out.
> Thanks in advance and best regards
> Isa

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