I am getting a MUMPS error in numerical factorization... Anyway, your B matrix is singular, with a high-dimensional nullspace. Maybe this is producing small negative values when computing v'*B*v. There is no way to relax the check. You should solve the problem as non-symmetric. Or use Arpack if it works for you.
Jose > El 30 oct 2017, a las 17:16, Franck Houssen <franck.hous...@inria.fr> > escribió: > > I deal with domain decomposition. It was faster/easier to generate files with > 1 proc: I guess the "dirichlet" and "neumann" matrices are the same in this > case, so one get the same files in the end... I didn't realized that when I > sent the files. My mistake. > > At my side, when I use krylovschur, SLEPc fails using 1, 2, 4, 8, ... procs > (each proc performs a SLEPc solve that may fail or not - difficult to catch > one). For instance, I attached data of one failed domain out of 8 (8 MPI > procs): matrices are very close but different. Moreover, I added EPS logs of > the same run and domain but replacing krylovschur with arpack when SLEPc does > not fail (regarding your remark that B could be indefinite, I added > -mat_mumps_icntl_33 1 to get the determinant). > > Anyway, I don't expect you spend too much time on this. My understanding is > that there is no way to relax this check ? Correct ? > > Franck > > ----- Mail original ----- >> De: "Jose E. Roman" <jro...@dsic.upv.es> >> À: "Franck Houssen" <franck.hous...@inria.fr> >> Cc: "For users of the development version of PETSc" <petsc-dev@mcs.anl.gov> >> Envoyé: Samedi 28 Octobre 2017 17:40:41 >> Objet: Re: [petsc-dev] SLEPc failure >> >> The two matrices are the same ... >> >>> El 28 oct 2017, a las 13:11, Franck Houssen <franck.hous...@inria.fr> >>> escribió: >>> >>> I just added that before EPSSetOperators: >>> PetscViewer viewerA; >>> PetscViewerBinaryOpen(PETSC_COMM_WORLD,"Atau.out",FILE_MODE_WRITE,&viewerA); >>> MatView(A,viewerA); >>> PetscViewer viewerB; >>> PetscViewerBinaryOpen(PETSC_COMM_WORLD,"Btau.out",FILE_MODE_WRITE,&viewerB); >>> MatView(B,viewerB); >>> >>> At first, I avoided binary as I didn't know if the format handles >>> big/little endianness... So I prefered ASCII. >>> >>> Binary data are attached. >>> >>> Franck >>> >>> PS : running debian with little endian. >>>>> python -c "import sys;print(0 if sys.byteorder=='big' else 1)" >>> 1 >>> >>> >>> ----- Mail original ----- >>>> De: "Jose E. Roman" <jro...@dsic.upv.es> >>>> À: "Franck Houssen" <franck.hous...@inria.fr> >>>> Cc: "For users of the development version of PETSc" >>>> <petsc-dev@mcs.anl.gov> >>>> Envoyé: Vendredi 27 Octobre 2017 18:52:56 >>>> Objet: Re: [petsc-dev] SLEPc failure >>>> >>>> I cannot load the files you sent. Please send the matrices in binary >>>> format. >>>> The easiest way is to run your program with -eps_view_mat0 binary:Atau.bin >>>> -eps_view_mat1 binary:Btau.bin >>>> >>>> However, the files are written at the end of EPSSolve() so if the solve >>>> fails >>>> then it will not create the files. You can try running with -eps_max_it 1 >>>> or add code in your main program to write the matrices. >>>> >>>> Jose >>>> >>>> >>>>> El 27 oct 2017, a las 12:28, Franck Houssen <franck.hous...@inria.fr> >>>>> escribió: >>>>> >>>>> Maybe could be convenient for the users to have an option (or an >>>>> EPSSetXXX) >>>>> to relax that check ? >>>>> Data are attached. >>>>> >>>>> Franck >>>>> >>>>> ----- Mail original ----- >>>>>> De: "Jose E. Roman" <jro...@dsic.upv.es> >>>>>> À: "Franck Houssen" <franck.hous...@inria.fr> >>>>>> Cc: "For users of the development version of PETSc" >>>>>> <petsc-dev@mcs.anl.gov> >>>>>> Envoyé: Vendredi 27 Octobre 2017 10:15:44 >>>>>> Objet: Re: [petsc-dev] SLEPc failure >>>>>> >>>>>> There is no new option. What I mean is that from 3.7 to 3.8 we changed >>>>>> the >>>>>> line that produces this error. But it seems that it is still failing in >>>>>> your >>>>>> problem. Maybe your B matrix is indefinite or not exactly symmetric. Can >>>>>> you >>>>>> send me the matrices? >>>>>> Jose >>>>>> >>>>>>> El 27 oct 2017, a las 9:57, Franck Houssen <franck.hous...@inria.fr> >>>>>>> escribió: >>>>>>> >>>>>>> I use the development version (bitbucket clone). How to relax the check >>>>>>> ? >>>>>>> At command line option ? >>>>>>> >>>>>>> Franck >>>>>>> >>>>>>> ----- Mail original ----- >>>>>>>> De: "Jose E. Roman" <jro...@dsic.upv.es> >>>>>>>> À: "Franck Houssen" <franck.hous...@inria.fr> >>>>>>>> Cc: "For users of the development version of PETSc" >>>>>>>> <petsc-dev@mcs.anl.gov> >>>>>>>> Envoyé: Jeudi 26 Octobre 2017 18:49:22 >>>>>>>> Objet: Re: [petsc-dev] SLEPc failure >>>>>>>> >>>>>>>> >>>>>>>>> El 26 oct 2017, a las 18:36, Franck Houssen <franck.hous...@inria.fr> >>>>>>>>> escribió: >>>>>>>>> >>>>>>>>> Here is a stack I end up with when trying to solve an eigen problem >>>>>>>>> (real, >>>>>>>>> sym, generalized) with SLEPc. My understanding is that, during the >>>>>>>>> Gram >>>>>>>>> Schmidt orthogonalisation, the projection of one basis vector turns >>>>>>>>> out >>>>>>>>> to >>>>>>>>> be null. >>>>>>>>> First, is this correct ? Second, in such cases, are there some >>>>>>>>> recommended >>>>>>>>> "recipe" to test/try (options) to get a clue on the problem ? (I >>>>>>>>> would >>>>>>>>> unfortunately perfectly understand the answer could be no !... As >>>>>>>>> this >>>>>>>>> totally depends on A/B). >>>>>>>>> >>>>>>>>> With arpack, the eigen problem is solved (so the matrix A and B I use >>>>>>>>> seems >>>>>>>>> to be relevant). But, when I change from arpack to >>>>>>>>> krylovschur/ciss/arnoldi, I get the stack below. >>>>>>>>> >>>>>>>>> Franck >>>>>>>>> >>>>>>>>> [0]PETSC ERROR: #1 BV_SafeSqrt() >>>>>>>>> [0]PETSC ERROR: #2 BVNorm_Private() >>>>>>>>> [0]PETSC ERROR: #3 BVNormColumn() >>>>>>>>> [0]PETSC ERROR: #4 BV_NormVecOrColumn() >>>>>>>>> [0]PETSC ERROR: #5 BVOrthogonalizeCGS1() >>>>>>>>> [0]PETSC ERROR: #6 BVOrthogonalizeGS() >>>>>>>>> [0]PETSC ERROR: #7 BVOrthonormalizeColumn() >>>>>>>>> [0]PETSC ERROR: #8 EPSFullLanczos() >>>>>>>>> [0]PETSC ERROR: #9 EPSSolve_KrylovSchur_Symm() >>>>>>>>> [0]PETSC ERROR: #10 EPSSolve() >>>>>>>> >>>>>>>> Is this with SLEPc 3.8? In SLEPc 3.8 we relaxed this check so I would >>>>>>>> suggest >>>>>>>> trying with it. >>>>>>>> Jose >>>>>>>> >>>>>>>> >>>>>> >>>>>> >>>>> <ABtau.tar.gz> >>>> >>>> >>> <ABtau.tar.gz> >> >> > <slepc.tar.gz>