Hi, Again about prescribed boundary condition issue. >>>> So my quick follow up question is How a displacement-controled load is >>>> done corrently in Petsc 2.3.3? >>> >>> To do it in 2.3.3 simply have for those components of F() the formula >>> F_i = x_i - givenvalue_i and in your Jacobian just use MatZeroRows() for >>> those rows >>>
in a nonlinear solving, I followed the above suggestion: in FormFunction, set F_i=x_i-given_value (nonzero) and in FormJacobian, MatZeroRows for the corresponding rows. However, the convergence is must slowed down as the exact satisfaction of xi=givenvalue has to be satisfied in an interative manner. Acturally convergence is not just slow but almost not practical (normally > 50 interations). Am I am missing something? Rong ----- Original Message ----- From: "Tian(ICT)" <[email protected]> To: "PETSc users list" <petsc-users at mcs.anl.gov> Sent: Wednesday, May 11, 2011 2:16 PM Subject: Re: [petsc-users] nonzero prescribed boundary condition > With additional -snes_type test: > > "-pc_type > lu -ksp_monitor_true_residual -snes_monitor -ksp_monitor -snes_type test" > > atol=1e-050, rtol=1e-008, stol=1e-008, maxit=50, maxf=10000 > Testing hand-coded Jacobian, if the ratio is > O(1.e-8), the hand-coded Jacobian is probably correct. > Run with -snes_test_display to show difference > of hand-coded and finite difference Jacobian. > Norm of matrix ratio 9.05702e-008 difference 3.94971 > Norm of matrix ratio 3.6015e-007 difference 15.7059 > Norm of matrix ratio 3.73941e-007 difference 16.3073 > [0]PETSC ERROR: SNESSolve() line 1871 in > src/snes/interface/C:\cygwin\home\PETSC-~1.3-P\src\snes\INTERF~1\snes.c > [0]PETSC ERROR: User provided function() line 572 in > unknowndirectory/c:\cygwin\home\rabbit\pgfem - csrbf\domain.cpp > [0]PETSC ERROR: User provided function() line 40 in > unknowndirectory/c:\cygwin\home\rabbit\pgfem - csrbf\main.cpp > > > -snes_mf_operator does not work: > > "-pc_type > lu -ksp_monitor_true_residual -snes_monitor -ksp_monitor -snes_ms_operator" > > [0]PETSC ERROR: --------------------- Error > Message ------------------------------------ > [0]PETSC ERROR: Object is in wrong state! > [0]PETSC ERROR: Not for unassembled matrix! > [0]PETSC > ERROR: > ------------------------------------------------------------------------ > [0]PETSC ERROR: Petsc Release Version 2.3.3, Patch 15, Tue Sep 23 10:02:49 > CDT 2008 HG revision: 31306062cd1a6f6a2496fccb4878f485c9b91760 > [0]PETSC ERROR: See docs/changes/index.html for recent updates. > [0]PETSC ERROR: See docs/faq.html for hints about trouble shooting. > [0]PETSC ERROR: See docs/index.html for manual pages. > [0]PETSC > ERROR: > ------------------------------------------------------------------------ > [0]PETSC ERROR: pgfem on a cygwin-gc named RTI458-LAPTOP by rabbit Wed May > 11 14:16:08 2011 > [0]PETSC ERROR: Libraries linked from /home/petsc-2.3.3-p15/lib/cygwin-gcc > [0]PETSC ERROR: Configure run at Wed Dec 1 17:02:20 2010 > [0]PETSC ERROR: Configure options --with-cc="win32fe > cl" --with-cxx="win32fe > cl" --download-c-blas-lapack=1 --with-clanguage=cxx --with-fc=0 > --useThreads=0 > --with-shared=0 > [0]PETSC > ERROR: > ------------------------------------------------------------------------ > [0]PETSC ERROR: MatDuplicate() line 3218 in > src/mat/interface/C:\cygwin\home\PETSC-~1.3-P\src\mat\INTERF~1\matrix.c > atol=1e-050, rtol=1e-008, stol=1e-008, maxit=50, maxf=10000 > 0 SNES Function norm 7.071067811865e-002 > 0 KSP Residual norm 9.965778978387e-002 > [0]PETSC ERROR: --------------------- Error > Message ------------------------------------ > [0]PETSC ERROR: Null argument, when expecting valid pointer! > [0]PETSC ERROR: Null Object: Parameter # 1! > [0]PETSC > ERROR: > ------------------------------------------------------------------------ > [0]PETSC ERROR: Petsc Release Version 2.3.3, Patch 15, Tue Sep 23 10:02:49 > CDT 2008 HG revision: 31306062cd1a6f6a2496fccb4878f485c9b91760 > [0]PETSC ERROR: See docs/changes/index.html for recent updates. > [0]PETSC ERROR: See docs/faq.html for hints about trouble shooting. > [0]PETSC ERROR: See docs/index.html for manual pages. > [0]PETSC > ERROR: > ------------------------------------------------------------------------ > [0]PETSC ERROR: pgfem on a cygwin-gc named RTI458-LAPTOP by rabbit Wed May > 11 14:16:08 2011 > [0]PETSC ERROR: Libraries linked from /home/petsc-2.3.3-p15/lib/cygwin-gcc > [0]PETSC ERROR: Configure run at Wed Dec 1 17:02:20 2010 > [0]PETSC ERROR: Configure options --with-cc="win32fe > cl" --with-cxx="win32fe > cl" --download-c-blas-lapack=1 --with-clanguage=cxx --with-fc=0 > --useThreads=0 > --with-shared=0 > [0]PETSC > ERROR: > ------------------------------------------------------------------------ > [0]PETSC ERROR: PetscObjectGetComm() line 34 in > src/sys/objects/C:\cygwin\home\PETSC-~1.3-P\src\sys\objects\gcomm.c > [0]PETSC ERROR: VecNormBegin() line 495 in > src/vec/vec/utils/C:\cygwin\home\PETSC-~1.3-P\src\vec\vec\utils\comb.c > [0]PETSC ERROR: MatMFFDCompute_WP() line 73 in > src/mat/impls/mffd/C:\cygwin\home\PETSC-~1.3-P\src\mat\impls\mffd\wp.c > [0]PETSC ERROR: MatMult_MFFD() line 294 in > src/mat/impls/mffd/C:\cygwin\home\PETSC-~1.3-P\src\mat\impls\mffd\mffd.c > [0]PETSC ERROR: MatMult() line 1632 in > src/mat/interface/C:\cygwin\home\PETSC-~1.3-P\src\mat\INTERF~1\matrix.c > [0]PETSC ERROR: KSPDefaultBuildResidual() line 605 in > src/ksp/ksp/interface/C:\cygwin\home\PETSC-~1.3-P\src\ksp\ksp\INTERF~1\iterativ.c > [0]PETSC ERROR: KSPBuildResidual() line 1587 in > src/ksp/ksp/interface/C:\cygwin\home\PETSC-~1.3-P\src\ksp\ksp\INTERF~1\itfunc.c > [0]PETSC ERROR: KSPMonitorTrueResidualNorm() line 258 in > src/ksp/ksp/interface/C:\cygwin\home\PETSC-~1.3-P\src\ksp\ksp\INTERF~1\iterativ.c > [0]PETSC ERROR: GMREScycle() line 155 in > src/ksp/ksp/impls/gmres/C:\cygwin\home\PETSC-~1.3-P\src\ksp\ksp\impls\gmres\gmres.c > [0]PETSC ERROR: KSPSolve_GMRES() line 241 in > src/ksp/ksp/impls/gmres/C:\cygwin\home\PETSC-~1.3-P\src\ksp\ksp\impls\gmres\gmres.c > [0]PETSC ERROR: KSPSolve() line 379 in > src/ksp/ksp/interface/C:\cygwin\home\PETSC-~1.3-P\src\ksp\ksp\INTERF~1\itfunc.c > [0]PETSC ERROR: SNES_KSPSolve() line 2578 in > src/snes/interface/C:\cygwin\home\PETSC-~1.3-P\src\snes\INTERF~1\snes.c > [0]PETSC ERROR: SNESSolve_LS() line 184 in > src/snes/impls/ls/C:\cygwin\home\PETSC-~1.3-P\src\snes\impls\ls\ls.c > [0]PETSC ERROR: SNESSolve() line 1871 in > src/snes/interface/C:\cygwin\home\PETSC-~1.3-P\src\snes\INTERF~1\snes.c > [0]PETSC ERROR: User provided function() line 574 in > unknowndirectory/c:\cygwin\home\rabbit\pgfem - csrbf\domain.cpp > [0]PETSC ERROR: User provided function() line 40 in > unknowndirectory/c:\cygwin\home\rabbit\pgfem - csrbf\main.cpp > > > Rong > > ----- Original Message ----- > From: "Barry Smith" <bsmith at mcs.anl.gov> > To: "PETSc users list" <petsc-users at mcs.anl.gov> > Sent: Wednesday, May 11, 2011 11:05 AM > Subject: Re: [petsc-users] nonzero prescribed boundary condition > > > > Ok, the linear solver looks like it is working ok. The likely problem is > that Jacobian does not match the function evaluation. > > Run the same thing but with the additional option -snes_mf_operator > > Then run with -snes_type test (instead of -snes_mf_operator). > > Barry > > On May 10, 2011, at 8:14 PM, Tian(ICT) wrote: > >> Dear Barry, here is the output using -pc_type >> lu -ksp_monitor_true_residual -snes_monitor -ksp_monitor >> the attached is the same and for clear reference. Thanks again for helps. >> >> atol=1e-050, rtol=1e-008, stol=1e-008, maxit=50, maxf=10000 >> 0 SNES Function norm 7.071067811865e-002 >> 0 KSP Residual norm 9.965778978387e-002 >> 0 KSP preconditioned resid norm 9.965778978387e-002 true resid norm >> 7.071067811865e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 6.823187455811e-017 >> 1 KSP preconditioned resid norm 6.823187455811e-017 true resid norm >> 8.847298885656e-011 ||Ae||/||Ax|| 1.251197007446e-009 >> 1 SNES Function norm 6.401926523423e-002 >> 0 KSP Residual norm 8.969200212486e-002 >> 0 KSP preconditioned resid norm 8.969200212486e-002 true resid norm >> 6.401926523423e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 1.106757475780e-016 >> 1 KSP preconditioned resid norm 1.106757475780e-016 true resid norm >> 6.211830067439e-011 ||Ae||/||Ax|| 9.703063671087e-010 >> 2 SNES Function norm 5.849992149767e-002 >> 0 KSP Residual norm 8.072279488157e-002 >> 0 KSP preconditioned resid norm 8.072279488157e-002 true resid norm >> 5.849992149767e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 1.268750073799e-017 >> 1 KSP preconditioned resid norm 1.268750073799e-017 true resid norm >> 3.802431036387e-011 ||Ae||/||Ax|| 6.499890835816e-010 >> 3 SNES Function norm 5.376618503592e-002 >> 0 KSP Residual norm 7.265050969883e-002 >> 0 KSP preconditioned resid norm 7.265050969883e-002 true resid norm >> 5.376618503592e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 2.677655733356e-017 >> 1 KSP preconditioned resid norm 2.677655733356e-017 true resid norm >> 8.120397788686e-011 ||Ae||/||Ax|| 1.510316899602e-009 >> 4 SNES Function norm 4.956894354459e-002 >> 0 KSP Residual norm 6.538545411661e-002 >> 0 KSP preconditioned resid norm 6.538545411661e-002 true resid norm >> 4.956894354459e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 9.557004153175e-017 >> 1 KSP preconditioned resid norm 9.557004153175e-017 true resid norm >> 2.944250802029e-011 ||Ae||/||Ax|| 5.939708598754e-010 >> 5 SNES Function norm 4.575418613137e-002 >> 0 KSP Residual norm 5.884690496914e-002 >> 0 KSP preconditioned resid norm 5.884690496914e-002 true resid norm >> 4.575418613137e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 5.470969262115e-017 >> 1 KSP preconditioned resid norm 5.470969262115e-017 true resid norm >> 3.659003166095e-011 ||Ae||/||Ax|| 7.997089393284e-010 >> 6 SNES Function norm 4.223022245585e-002 >> 0 KSP Residual norm 5.296221144636e-002 >> 0 KSP preconditioned resid norm 5.296221144636e-002 true resid norm >> 4.223022245585e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 8.255198782390e-017 >> 1 KSP preconditioned resid norm 8.255198782390e-017 true resid norm >> 1.955545658933e-011 ||Ae||/||Ax|| 4.630678090739e-010 >> 7 SNES Function norm 3.894430065910e-002 >> 0 KSP Residual norm 4.766598785088e-002 >> 0 KSP preconditioned resid norm 4.766598785088e-002 true resid norm >> 3.894430065910e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 3.322615478395e-017 >> 1 KSP preconditioned resid norm 3.322615478395e-017 true resid norm >> 3.485328148673e-011 ||Ae||/||Ax|| 8.949520442496e-010 >> 8 SNES Function norm 3.586683371135e-002 >> 0 KSP Residual norm 4.289938708067e-002 >> 0 KSP preconditioned resid norm 4.289938708067e-002 true resid norm >> 3.586683371135e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 6.181358328498e-017 >> 1 KSP preconditioned resid norm 6.181358328498e-017 true resid norm >> 3.246902818086e-011 ||Ae||/||Ax|| 9.052660862724e-010 >> 9 SNES Function norm 3.298130202025e-002 >> 0 KSP Residual norm 3.860944676473e-002 >> 0 KSP preconditioned resid norm 3.860944676473e-002 true resid norm >> 3.298130202025e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 4.635174776374e-017 >> 1 KSP preconditioned resid norm 4.635174776374e-017 true resid norm >> 1.497516842272e-011 ||Ae||/||Ax|| 4.540502498513e-010 >> 10 SNES Function norm 3.027806208930e-002 >> 0 KSP Residual norm 3.474850078591e-002 >> 0 KSP preconditioned resid norm 3.474850078591e-002 true resid norm >> 3.027806208930e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 2.389914053685e-017 >> 1 KSP preconditioned resid norm 2.389914053685e-017 true resid norm >> 6.007440888596e-011 ||Ae||/||Ax|| 1.984090286517e-009 >> 11 SNES Function norm 2.749422924729e-002 >> 0 KSP Residual norm 3.081350823297e-002 >> 0 KSP preconditioned resid norm 3.081350823297e-002 true resid norm >> 2.749422924729e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 2.640567497647e-017 >> 1 KSP preconditioned resid norm 2.640567497647e-017 true resid norm >> 1.281638295853e-011 ||Ae||/||Ax|| 4.661481085089e-010 >> 12 SNES Function norm 2.437488247885e-002 >> 0 KSP Residual norm 2.633007441879e-002 >> 0 KSP preconditioned resid norm 2.633007441879e-002 true resid norm >> 2.437488247885e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 2.772331460094e-017 >> 1 KSP preconditioned resid norm 2.772331460094e-017 true resid norm >> 1.918212496143e-011 ||Ae||/||Ax|| 7.869627670236e-010 >> 13 SNES Function norm 2.079664278637e-002 >> 0 KSP Residual norm 2.104738289397e-002 >> 0 KSP preconditioned resid norm 2.104738289397e-002 true resid norm >> 2.079664278637e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 1.650632708670e-017 >> 1 KSP preconditioned resid norm 1.650632708670e-017 true resid norm >> 2.316371967362e-011 ||Ae||/||Ax|| 1.113820144509e-009 >> 14 SNES Function norm 1.657344626858e-002 >> 0 KSP Residual norm 1.454141853505e-002 >> 0 KSP preconditioned resid norm 1.454141853505e-002 true resid norm >> 1.657344626858e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 1.129401160070e-017 >> 1 KSP preconditioned resid norm 1.129401160070e-017 true resid norm >> 7.885499327559e-012 ||Ae||/||Ax|| 4.757911661686e-010 >> 15 SNES Function norm 1.484243752612e-002 >> 0 KSP Residual norm 5.241948491751e-009 >> 0 KSP preconditioned resid norm 5.241948491751e-009 true resid norm >> 1.484243752612e-002 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 2.729506849025e-024 >> 1 KSP preconditioned resid norm 2.729506849025e-024 true resid norm >> 6.386677851085e-018 ||Ae||/||Ax|| 4.302984492839e-016 >> 16 SNES Function norm 2.828002157497e-008 >> 0 KSP Residual norm 6.042518362322e-015 >> 0 KSP preconditioned resid norm 6.042518362322e-015 true resid norm >> 2.828002157497e-008 ||Ae||/||Ax|| 1.000000000000e+000 >> 1 KSP Residual norm 6.272441346127e-030 >> 1 KSP preconditioned resid norm 6.272441346127e-030 true resid norm >> 1.112857698032e-023 ||Ae||/||Ax|| 3.935137372797e-016 >> 17 SNES Function norm 2.960967020289e-008 >> STEP 0 (Newton iterations: 17) >> >> diverged reason: -6 >> >> >> ----- Original Message ----- From: "Barry Smith" <bsmith at mcs.anl.gov> >> To: "PETSc users list" <petsc-users at mcs.anl.gov> >> Sent: Wednesday, May 11, 2011 2:54 AM >> Subject: Re: [petsc-users] nonzero prescribed boundary condition >> >> >> >> Use -pc_type lu -ksp_monitor_true_residual -snes_monitor -ksp_monitor >> and >> send the outputs >> >> >> Barry >> >> On May 9, 2011, at 10:43 PM, Tian(ICT) wrote: >> >>> by the way, the increment size is like that >>> for a 100 lengh model, the increment is set to 0.05, >>> the engineering strain is around 5%% per load step. >>> This is already too small increment size for a large deformation >>> analysis. >>> a 0.5 increment size leads to both linear search and trust region >>> failed. >>> linear search failed for 0.05 while trust region converges with 17 >>> Newton >>> iterations each load step. >>> Rong >>> >>> ----- Original Message ----- From: "Tian(ICT)" <rongtian at ncic.ac.cn> >>> To: "PETSc users list" <petsc-users at mcs.anl.gov> >>> Sent: Tuesday, May 10, 2011 11:37 AM >>> Subject: Re: [petsc-users] nonzero prescribed boundary condition >>> >>> >>>> First, thanks again, the issue was gone. >>>> >>>> I just followed up with some test results. >>>> I have tested SNES using one finite element for a geometric large >>>> deformation problem. >>>> Those are just the very early test results so they may be not telling >>>> what happened exactly. >>>> For the displacement controlled load, I found that convergence is much >>>> slower than that of force loading. >>>> Even worse, linear search is so sensitive to the displacement increment >>>> and diverged no matter what the increment size was used (too small >>>> incremnt also led to diverged soloution (-6 reason), trust region works >>>> well in the sense of not sensitive to the displacement increment, but >>>> during each load step, it requires around ten to several tens of Newton >>>> interations whereas for the force loading case and the almost same >>>> amount of deformation, this is normally 3. This is against my >>>> expectation. Any hint? >>>> >>>> Rong >>>> >>>> ----- Original Message ----- From: "Barry Smith" <bsmith at mcs.anl.gov> >>>> To: "PETSc users list" <petsc-users at mcs.anl.gov> >>>> Sent: Tuesday, May 10, 2011 10:22 AM >>>> Subject: Re: [petsc-users] nonzero prescribed boundary condition >>>> >>>> >>>> >>>> On May 9, 2011, at 9:15 PM, Tian(ICT) wrote: >>>> >>>>> Dear Barry, Thanks a lot for quick answering. >>>>> I checked the development documents and found the new version of >>>>> MatZeroRows() does support the nonzero prescribed boundary conditions. >>>>> >>>>> I followed up with more details. >>>>> I am using Petasc 2.3.3. to solve a nonlinear problem, e.g. using SNES >>>>> solvers. >>>>> I used a displacement-controlled load (as this type of loading works >>>>> well for all cases). >>>>> This is the reason the nonzero prescribed boundary came up. >>>>> >>>>> In FormJacobian, I modified Jacobian and residual to satisfy the >>>>> nonzero prescribed boundary. >>>>> In FormFunction, I modified the solution to the known solution(this >>>>> should not be necessary as the modified Jacobian and rhs should give >>>>> the prescribed solution also) >>>> >>>> You should not do it this way. See below. >>>>> >>>>> Now I found another issue, no matter if I prescried the solution or >>>>> not >>>>> in FormFunction, >>>>> SNES solver always call FormFunction and never call FormJacobian. >>>> >>>> The only reason it would not call FormJacobian is if decided that the >>>> residual norm was small enough before any Newton steps; for example if >>>> the FormFunction() computed exactly the zero function initially. When >>>> you run with -snes_monitor -ksp_monitor what does it print for residual >>>> norms. >>>> >>>>> Of course the solver finally diverged or converged to a zero solution. >>>>> >>>>> So my quick follow up question is How a displacement-controled load is >>>>> done corrently in Petsc 2.3.3? >>>> >>>> To do it in 2.3.3 simply have for those components of F() the formula >>>> F_i = x_i - givenvalue_i and in your Jacobian just use MatZeroRows() >>>> for >>>> those rows >>>> >>>> We strongly urge you to upgrade to the latest PETSc before doing >>>> anything further. >>>> >>>> >>>> Barry >>>> >>>>> >>>>> Rong >>>>> >>>>> ----- Original Message ----- From: "Barry Smith" <bsmith at mcs.anl.gov> >>>>> To: "PETSc users list" <petsc-users at mcs.anl.gov> >>>>> Sent: Tuesday, May 10, 2011 9:31 AM >>>>> Subject: Re: [petsc-users] nonzero prescribed boundary condition >>>>> >>>>> >>>>> >>>>> In petsc-dev >>>>> http://www.mcs.anl.gov/petsc/petsc-as/developers/index.html we have >>>>> modified the calling sequence for MatZeroRows() so that it can >>>>> automatically adjust the appropriate right hand side values for the >>>>> zeroed rows to support zero or non-zero prescribed boundary conditions >>>>> easily. >>>>> >>>>> Barry >>>>> >>>>> On May 9, 2011, at 8:18 PM, Tian(ICT) wrote: >>>>> >>>>>> Dear all, >>>>>> >>>>>> I got this question long ago and searched the prior posting but did >>>>>> not find the solution. >>>>>> The question is about nonzero prescribed boundary condition. >>>>>> My understanding is that MatZeroRows() works only for zero prescribed >>>>>> value, not non-zero value. >>>>>> For the non-zero values, we have to remove the rows associated with >>>>>> the boundary, but this >>>>>> will lead to a zero dignal and accordingly the rows in r.h.s should >>>>>> also be removed. >>>>>> My question is that does MatZeroRows() also works for nonzero >>>>>> prescribed boundary and if so how to do it simply? >>>>>> >>>>>> Rong >>>>> >>>>> >>>> >>>> >>> >> >> <aa> > > >
