Beats me :-) Just set it to whatever the DMDA sets it too Barry
> On Dec 10, 2024, at 11:20 AM, Matteo Semplice <matteo.sempl...@uninsubria.it> > wrote: > > Thanks, Barry. > > Just to be sure, one should refer to the help of > https://urldefense.us/v3/__https://petsc.org/release/manualpages/DM/DMCreateInterpolationScale/__;!!G_uCfscf7eWS!adeZHH1r8zFo3A5H1wpZDveIiI1ryL_lOJwl2MsOC0uuANOMda4SvkEHBjoh9sZgxTrk1G2RbGRejVvgyba9OYQ$ > and the vec should be set to the point-wise inverse of > (INTERPOLATION)*(vector of ones) ? > > Matteo > > On 10/12/2024 16:38, Barry Smith wrote: >> >> It appears you are completely ignoring the vec argument? Take a look at, >> for example, DMCreateInterpolation_DA() you will see you need to provide an >> appropriate vec in the same way you need (and do) provide an appropriate mat. >> >> Barry >> >> >>> On Dec 10, 2024, at 7:02 AM, Matteo Semplice via petsc-users >>> <petsc-users@mcs.anl.gov> <mailto:petsc-users@mcs.anl.gov> wrote: >>> >>> Dear petsc-users, >>> >>> I am trying with a student to modify the MG example 65 to use >>> mat-shells instead of assembled matrices. Our use case is for a method that >>> will use custom shell operators and shell interpolation/restrictions. >>> >>> To start we have modified ex65 and tried to replace the standard >>> restriction/interpolation with a shell matrix that performs the same >>> operations on the DMDA grids. >>> >>> I attach our modifications to ex65. >>> >>> The problem is that the code sometimes completes execution and sometimes >>> errors out like >>> >>> $ ./ex65shell -ksp_monitor -pc_type mg -da_refine 2 -ksp_rtol 1e-1 >>> >> Created DMshell 0x55bbc83c91a0 (0x55bbc8390a80) >>> Calling KSPSolve from main >>> computeRHS on grid 513 >>> computeMatrix on grid 513 >>> Inside Coarsen >>> >> Created DMshell 0x55bbc84c5270 (0x55bbc84b2ff0) >>> Inside Coarsen >>> >> Created DMshell 0x55bbc84e0a30 (0x55bbc84bdb60) >>> >> Create interpolation from 0x55bbc84c5270(0x55bbc84b2ff0) to >>> >> 0x55bbc83c91a0(0x55bbc8390a80) >>> [0]PETSC ERROR: --------------------- Error Message >>> -------------------------------------------------------------- >>> [0]PETSC ERROR: Invalid pointer >>> [0]PETSC ERROR: Invalid Pointer to PetscObject: Argument 'obj' (parameter # >>> 1) >>> [0]PETSC ERROR: See >>> https://urldefense.us/v3/__https://petsc.org/release/faq/__;!!G_uCfscf7eWS!adeZHH1r8zFo3A5H1wpZDveIiI1ryL_lOJwl2MsOC0uuANOMda4SvkEHBjoh9sZgxTrk1G2RbGRejVvgZJWXKXM$ >>> >>> <https://urldefense.us/v3/__https://petsc.org/release/faq/__;!!G_uCfscf7eWS!Y29qRoOD71oxcd-BQFTUohkIToMJNW3puZ3CerpZ6pBnecqhBQ8TBwhSnikLt4BYQTmsBgtKvoCFi-JuLXQAE_Oe_a_d2XOL8KvOmw$> >>> for trouble shooting. >>> [0]PETSC ERROR: Petsc Release Version 3.22.0, unknown >>> [0]PETSC ERROR: ./ex65shell with 1 MPI process(es) and PETSC_ARCH on >>> signalkuppe by matteo Tue Dec 10 12:55:12 2024 >>> [0]PETSC ERROR: Configure options: >>> --prefix=/home/matteo/software/petscsaved/3.22-opt/ >>> PETSC_DIR=/home/matteo/software/petsc --PETSC_ARCH=dbg --with-debugging=1 >>> --with-st >>> rict-petscerrorcode --download-hdf5 --download-ml --with-metis >>> --with-parmetis --with-gmsh --with-triangle --with-zlib >>> --with-p4est-dir=~/software/p4est/local/ >>> [0]PETSC ERROR: #1 PetscObjectReference() at >>> /home/matteo/software/petsc/src/sys/objects/inherit.c:620 >>> [0]PETSC ERROR: #2 PCMGSetRScale() at >>> /home/matteo/software/petsc/src/ksp/pc/impls/mg/mgfunc.c:394 >>> [0]PETSC ERROR: #3 PCSetUp_MG() at >>> /home/matteo/software/petsc/src/ksp/pc/impls/mg/mg.c:998 >>> [0]PETSC ERROR: #4 PCSetUp() at >>> /home/matteo/software/petsc/src/ksp/pc/interface/precon.c:1071 >>> [0]PETSC ERROR: #5 KSPSetUp() at >>> /home/matteo/software/petsc/src/ksp/ksp/interface/itfunc.c:415 >>> [0]PETSC ERROR: #6 KSPSolve_Private() at >>> /home/matteo/software/petsc/src/ksp/ksp/interface/itfunc.c:826 >>> [0]PETSC ERROR: #7 KSPSolve() at >>> /home/matteo/software/petsc/src/ksp/ksp/interface/itfunc.c:1075 >>> [0]PETSC ERROR: #8 main() at ../src/ex65shell.c:79 >>> [0]PETSC ERROR: PETSc Option Table entries: >>> [0]PETSC ERROR: -da_refine 2 (source: command line) >>> [0]PETSC ERROR: -ksp_monitor (source: command line) >>> [0]PETSC ERROR: -ksp_rtol 1e-1 (source: command line) >>> [0]PETSC ERROR: -pc_type mg (source: command line) >>> [0]PETSC ERROR: ----------------End of Error Message -------send entire >>> error message to petsc-ma...@mcs.anl.gov >>> <mailto:petsc-ma...@mcs.anl.gov>---------- >>> >>> In all cases valgrind complains like >>> >>> $ valgrind ./ex65shell -ksp_monitor -pc_type mg -da_refine 2 -ksp_rtol 1e-1 >>> -int_view ascii::ascii_info >>> ==2130767== Memcheck, a memory error detector >>> ==2130767== Copyright (C) 2002-2022, and GNU GPL'd, by Julian Seward et al. >>> ==2130767== Using Valgrind-3.19.0 and LibVEX; rerun with -h for copyright >>> info >>> ==2130767== Command: ./ex65shell -ksp_monitor -pc_type mg -da_refine 2 >>> -ksp_rtol 1e-1 -int_view ascii::ascii_info >>> ==2130767== >>> hwloc x86 backend cannot work under Valgrind, disabling. >>> May be reenabled by dumping CPUIDs with hwloc-gather-cpuid >>> and reloading them under Valgrind with HWLOC_CPUID_PATH. >>> >> Created DMshell 0xfbf50f0 (0xfb49480) >>> Calling KSPSolve from main >>> computeRHS on grid 513 >>> computeMatrix on grid 513 >>> Inside Coarsen >>> >> Created DMshell 0xff404a0 (0xff062d0) >>> Inside Coarsen >>> >> Created DMshell 0xff78ca0 (0xff4a530) >>> >> Create interpolation from 0xff404a0(0xff062d0) to 0xfbf50f0(0xfb49480) >>> Mat Object: 1 MPI process >>> type: shell >>> rows=513, cols=257 >>> ==2130767== Conditional jump or move depends on uninitialised value(s) >>> ==2130767== at 0x83FDAAE: PCSetUp_MG (mg.c:998) >>> ==2130767== by 0x8620C04: PCSetUp (precon.c:1071) >>> ==2130767== by 0x7DA78D5: KSPSetUp (itfunc.c:415) >>> ==2130767== by 0x7DB2093: KSPSolve_Private (itfunc.c:826) >>> ==2130767== by 0x7DB7A53: KSPSolve (itfunc.c:1075) >>> ==2130767== by 0x10D2F7: main (ex65shell.c:79) >>> ==2130767== >>> ==2130767== Conditional jump or move depends on uninitialised value(s) >>> ==2130767== at 0x5794061: VecDestroy (vector.c:570) >>> ==2130767== by 0x83FDC36: PCSetUp_MG (mg.c:999) >>> ==2130767== by 0x8620C04: PCSetUp (precon.c:1071) >>> ==2130767== by 0x7DA78D5: KSPSetUp (itfunc.c:415) >>> ==2130767== by 0x7DB2093: KSPSolve_Private (itfunc.c:826) >>> ==2130767== by 0x7DB7A53: KSPSolve (itfunc.c:1075) >>> ==2130767== by 0x10D2F7: main (ex65shell.c:79) >>> ==2130767== >>> >>> We are clearly doing something wrong since PCSetUp_MG (mg.c:998) is an >>> area of code where I wouldn't expect we would enter. >>> >>> Can you advise on the proper way to achieve our goal? >>> >>> Best regards >>> >>> Matteo >>> >>> <ex65.patch> >> > -- > Prof. Matteo Semplice > Università degli Studi dell’Insubria > Dipartimento di Scienza e Alta Tecnologia – DiSAT > Professore Associato > Via Valleggio, 11 – 22100 Como (CO) – Italia > tel.: +39 031 2386316
