[petsc-users] nonzero prescribed boundary condition
Tian(ICT)
rongtian at ncic.ac.cn
Wed May 11 08:44:21 CDT 2011
C:\cygwin\home\rabbit\pGFEM-test>pgfem -pc_type
lu -ksp_monitor_true_residual -s
nes_monitor
atol=1e-050, rtol=1e-008, stol=1e-008, maxit=50, maxf=10000
0 SNES Function norm 7.071067811865e-002
0 KSP preconditioned resid norm 9.965778978387e-002 true resid norm
7.07106781
1865e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 6.823187455811e-017 true resid norm
8.84729888
5656e-011 ||Ae||/||Ax|| 1.251197007446e-009
1 SNES Function norm 6.401926523423e-002
0 KSP preconditioned resid norm 8.969200212486e-002 true resid norm
6.40192652
3423e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 1.106757475780e-016 true resid norm
6.21183006
7439e-011 ||Ae||/||Ax|| 9.703063671087e-010
2 SNES Function norm 5.849992149767e-002
0 KSP preconditioned resid norm 8.072279488157e-002 true resid norm
5.84999214
9767e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 1.268750073799e-017 true resid norm
3.80243103
6387e-011 ||Ae||/||Ax|| 6.499890835816e-010
3 SNES Function norm 5.376618503592e-002
0 KSP preconditioned resid norm 7.265050969883e-002 true resid norm
5.37661850
3592e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 2.677655733356e-017 true resid norm
8.12039778
8686e-011 ||Ae||/||Ax|| 1.510316899602e-009
4 SNES Function norm 4.956894354459e-002
0 KSP preconditioned resid norm 6.538545411661e-002 true resid norm
4.95689435
4459e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 9.557004153175e-017 true resid norm
2.94425080
2029e-011 ||Ae||/||Ax|| 5.939708598754e-010
5 SNES Function norm 4.575418613137e-002
0 KSP preconditioned resid norm 5.884690496914e-002 true resid norm
4.57541861
3137e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 5.470969262115e-017 true resid norm
3.65900316
6095e-011 ||Ae||/||Ax|| 7.997089393284e-010
6 SNES Function norm 4.223022245585e-002
0 KSP preconditioned resid norm 5.296221144636e-002 true resid norm
4.22302224
5585e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 8.255198782390e-017 true resid norm
1.95554565
8933e-011 ||Ae||/||Ax|| 4.630678090739e-010
7 SNES Function norm 3.894430065910e-002
0 KSP preconditioned resid norm 4.766598785088e-002 true resid norm
3.89443006
5910e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 3.322615478395e-017 true resid norm
3.48532814
8673e-011 ||Ae||/||Ax|| 8.949520442496e-010
8 SNES Function norm 3.586683371135e-002
0 KSP preconditioned resid norm 4.289938708067e-002 true resid norm
3.58668337
1135e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 6.181358328498e-017 true resid norm
3.24690281
8086e-011 ||Ae||/||Ax|| 9.052660862724e-010
9 SNES Function norm 3.298130202025e-002
0 KSP preconditioned resid norm 3.860944676473e-002 true resid norm
3.29813020
2025e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 4.635174776374e-017 true resid norm
1.49751684
2272e-011 ||Ae||/||Ax|| 4.540502498513e-010
10 SNES Function norm 3.027806208930e-002
0 KSP preconditioned resid norm 3.474850078591e-002 true resid norm
3.02780620
8930e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 2.389914053685e-017 true resid norm
6.00744088
8596e-011 ||Ae||/||Ax|| 1.984090286517e-009
11 SNES Function norm 2.749422924729e-002
0 KSP preconditioned resid norm 3.081350823297e-002 true resid norm
2.74942292
4729e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 2.640567497647e-017 true resid norm
1.28163829
5853e-011 ||Ae||/||Ax|| 4.661481085089e-010
12 SNES Function norm 2.437488247885e-002
0 KSP preconditioned resid norm 2.633007441879e-002 true resid norm
2.43748824
7885e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 2.772331460094e-017 true resid norm
1.91821249
6143e-011 ||Ae||/||Ax|| 7.869627670236e-010
13 SNES Function norm 2.079664278637e-002
0 KSP preconditioned resid norm 2.104738289397e-002 true resid norm
2.07966427
8637e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 1.650632708670e-017 true resid norm
2.31637196
7362e-011 ||Ae||/||Ax|| 1.113820144509e-009
14 SNES Function norm 1.657344626858e-002
0 KSP preconditioned resid norm 1.454141853505e-002 true resid norm
1.65734462
6858e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 1.129401160070e-017 true resid norm
7.88549932
7559e-012 ||Ae||/||Ax|| 4.757911661686e-010
15 SNES Function norm 1.484243752612e-002
0 KSP preconditioned resid norm 5.241948491751e-009 true resid norm
1.48424375
2612e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 2.729506849025e-024 true resid norm
6.38667785
1085e-018 ||Ae||/||Ax|| 4.302984492839e-016
16 SNES Function norm 2.828002157497e-008
0 KSP preconditioned resid norm 6.042518362322e-015 true resid norm
2.82800215
7497e-008 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 6.272441346127e-030 true resid norm
1.11285769
8032e-023 ||Ae||/||Ax|| 3.935137372797e-016
17 SNES Function norm 2.960967020289e-008
STEP 0 (Newton iterations: 17)
diverged reason: -6
C:\cygwin\home\rabbit\pGFEM-test>
==================HOWEVER=================
-snes_type tr seems work
C:\cygwin\home\rabbit\pGFEM-test>pgfem -snes_type tr
atol=1e-050, rtol=1e-008, stol=1e-008, maxit=50, maxf=10000
STEP 0 (Newton iterations: 12)
STEP 1 (Newton iterations: 11)
STEP 2 (Newton iterations: 11)
...
STEP 70 (Newton iterations: 14)
^C
C:\cygwin\home\rabbit\pGFEM-test>
----- 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 9:02 PM
Subject: Re: [petsc-users] nonzero prescribed boundary condition
>> 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
Based on this it appears the Jacobian at the initial point is correct but
0 KSP preconditioned resid norm 9.965778978387e-002 true resid norm
7.071067811865e-002 ||Ae||/||Ax|| 1.000000000000e+000
1 KSP preconditioned resid norm 9.102368266281e-009 true resid norm
5.414197277222e-002 ||Ae||/||Ax|| 7.656831218811e-001
this indicates that the linear solver is not actually solving the linear
system. One would expect a large drop in the "true resid norm" and one does
not see that. This could be caused by
1) the computed Jacobian is wrong or
2) the Jacobian is singular and that is not being taken into account in the
linear solver.
Please rerun with the options -pc_type
lu -ksp_monitor_true_residual -snes_monitor BUT NOT THE
OPTION -snes_mf_operator and send the same output.
Barry
On May 11, 2011, at 1:46 AM, Tian(ICT) wrote:
> Pls ignore my previous email.
>
> The followings are the test results:
> the previous error in using -snes_mf_opertor was due to my own code.
> After modification, i.e. using different A and B and assemble both
> and in FormJacobian the native jacobian was assembled into B.
> Then with -snes_mf_operator led to the results shown below.
> The first three steps converged but with a diverged reason -6 at step 4.
>
>
> With additional -snes_type test, the results were
>
>> "-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
>>
>>
>> "-pc_type
>> lu -ksp_monitor_true_residual -snes_monitor -ksp_monitor -snes_ms_operator"
>
> 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 9.102368266281e-009
> 1 KSP preconditioned resid norm 9.102368266281e-009 true resid norm
> 5.414197277222e-002 ||Ae||/||Ax|| 7.656831218811e-001
> 1 SNES Function norm 6.401926196865e-002
> 0 KSP Residual norm 8.969200166800e-002
> 0 KSP preconditioned resid norm 8.969200166800e-002 true resid norm
> 6.401926196865e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 8.492849351675e-009
> 1 KSP preconditioned resid norm 8.492849351675e-009 true resid norm
> 1.400035213572e-002 ||Ae||/||Ax|| 2.186896834670e-001
> 2 SNES Function norm 5.849991037388e-002
> 0 KSP Residual norm 8.072279482667e-002
> 0 KSP preconditioned resid norm 8.072279482667e-002 true resid norm
> 5.849991037388e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.610510067555e-009
> 1 KSP preconditioned resid norm 3.610510067555e-009 true resid norm
> 4.757549946973e-003 ||Ae||/||Ax|| 8.132576471599e-002
> 3 SNES Function norm 5.376617142827e-002
> 0 KSP Residual norm 7.265050986128e-002
> 0 KSP preconditioned resid norm 7.265050986128e-002 true resid norm
> 5.376617142827e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 6.941165647221e-009
> 1 KSP preconditioned resid norm 6.941165647221e-009 true resid norm
> 3.935270526562e-002 ||Ae||/||Ax|| 7.319231446138e-001
> 4 SNES Function norm 4.956888929193e-002
> 0 KSP Residual norm 6.538545408372e-002
> 0 KSP preconditioned resid norm 6.538545408372e-002 true resid norm
> 4.956888929193e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.457970649220e-009
> 1 KSP preconditioned resid norm 3.457970649220e-009 true resid norm
> 2.037700110050e-002 ||Ae||/||Ax|| 4.110844804388e-001
> 5 SNES Function norm 4.575415001780e-002
> 0 KSP Residual norm 5.884690527647e-002
> 0 KSP preconditioned resid norm 5.884690527647e-002 true resid norm
> 4.575415001780e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 2.832662187541e-009
> 1 KSP preconditioned resid norm 2.832662187541e-009 true resid norm
> 1.662420124938e-002 ||Ae||/||Ax|| 3.633375604818e-001
> 6 SNES Function norm 4.223018337199e-002
> 0 KSP Residual norm 5.296221162333e-002
> 0 KSP preconditioned resid norm 5.296221162333e-002 true resid norm
> 4.223018337199e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.091667005099e-009
> 1 KSP preconditioned resid norm 3.091667005099e-009 true resid norm
> 2.235399010718e-002 ||Ae||/||Ax|| 5.293367994705e-001
> 7 SNES Function norm 3.894426990170e-002
> 0 KSP Residual norm 4.766598828506e-002
> 0 KSP preconditioned resid norm 4.766598828506e-002 true resid norm
> 3.894426990170e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 4.223811830585e-009
> 1 KSP preconditioned resid norm 4.223811830585e-009 true resid norm
> 2.831156780040e-002 ||Ae||/||Ax|| 7.269764684732e-001
> 8 SNES Function norm 3.586679674893e-002
> 0 KSP Residual norm 4.289938722959e-002
> 0 KSP preconditioned resid norm 4.289938722959e-002 true resid norm
> 3.586679674893e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.504535460429e-009
> 1 KSP preconditioned resid norm 3.504535460429e-009 true resid norm
> 2.254598873838e-002 ||Ae||/||Ax|| 6.286033541328e-001
> 9 SNES Function norm 3.298126871313e-002
> 0 KSP Residual norm 3.860944657267e-002
> 0 KSP preconditioned resid norm 3.860944657267e-002 true resid norm
> 3.298126871313e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 4.439084585574e-009
> 1 KSP preconditioned resid norm 4.439084585574e-009 true resid norm
> 6.936792391193e-003 ||Ae||/||Ax|| 2.103252137305e-001
> 10 SNES Function norm 3.027806037514e-002
> 0 KSP Residual norm 3.474850031738e-002
> 0 KSP preconditioned resid norm 3.474850031738e-002 true resid norm
> 3.027806037514e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.476854671229e-009
> 1 KSP preconditioned resid norm 3.476854671229e-009 true resid norm
> 1.935717696630e-002 ||Ae||/||Ax|| 6.393136391984e-001
> 11 SNES Function norm 2.775064646763e-002
> 0 KSP Residual norm 3.127364888698e-002
> 0 KSP preconditioned resid norm 3.127364888698e-002 true resid norm
> 2.775064646763e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 2.380857715198e-009
> 1 KSP preconditioned resid norm 2.380857715198e-009 true resid norm
> 1.646856223644e-002 ||Ae||/||Ax|| 5.934478771746e-001
> 12 SNES Function norm 2.430399371900e-002
> 0 KSP Residual norm 2.602654480862e-002
> 0 KSP preconditioned resid norm 2.602654480862e-002 true resid norm
> 2.430399371900e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 2.556142726483e-009
> 1 KSP preconditioned resid norm 2.556142726483e-009 true resid norm
> 1.794651743617e-002 ||Ae||/||Ax|| 7.384184526900e-001
> 13 SNES Function norm 2.029256664631e-002
> 0 KSP Residual norm 1.954645630691e-002
> 0 KSP preconditioned resid norm 1.954645630691e-002 true resid norm
> 2.029256664631e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.913585412092e-010
> 1 KSP preconditioned resid norm 3.913585412092e-010 true resid norm
> 1.903675728342e-003 ||Ae||/||Ax|| 9.381148089946e-002
> 14 SNES Function norm 1.566638821565e-002
> 0 KSP Residual norm 1.231404128086e-002
> 0 KSP preconditioned resid norm 1.231404128086e-002 true resid norm
> 1.566638821565e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 7.258598971379e-010
> 1 KSP preconditioned resid norm 7.258598971379e-010 true resid norm
> 1.221317129610e-003 ||Ae||/||Ax|| 7.795779810881e-002
> 15 SNES Function norm 1.064422587384e-002
> 0 KSP Residual norm 3.723145759360e-009
> 0 KSP preconditioned resid norm 3.723145759360e-009 true resid norm
> 1.064422587384e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 5.546825086207e-016
> 1 KSP preconditioned resid norm 5.546825086207e-016 true resid norm
> 2.984647735625e-009 ||Ae||/||Ax|| 2.804006389003e-007
> 16 SNES Function norm 9.689226075617e-008
> 0 KSP Residual norm 1.643080767133e-014
> 0 KSP preconditioned resid norm 1.643080767133e-014 true resid norm
> 9.689226075617e-008 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 7.291965935374e-022
> 1 KSP preconditioned resid norm 7.291965935374e-022 true resid norm
> 5.001850432973e-015 ||Ae||/||Ax|| 5.162280654758e-008
> 17 SNES Function norm 3.747290584108e-008
> STEP 0 (Newton iterations: 17)
>
> 0 SNES Function norm 7.071067811866e-002
> 0 KSP Residual norm 9.965769844003e-002
> 0 KSP preconditioned resid norm 9.965769844003e-002 true resid norm
> 7.071067811866e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 4.919247724727e-009
> 1 KSP preconditioned resid norm 4.919247724727e-009 true resid norm
> 2.073848008334e-002 ||Ae||/||Ax|| 2.932863979685e-001
> 1 SNES Function norm 6.402041310994e-002
> 0 KSP Residual norm 8.969192038029e-002
> 0 KSP preconditioned resid norm 8.969192038029e-002 true resid norm
> 6.402041310994e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 4.072962844649e-009
> 1 KSP preconditioned resid norm 4.072962844649e-009 true resid norm
> 2.116458841832e-002 ||Ae||/||Ax|| 3.305912503559e-001
> 2 SNES Function norm 5.850358277995e-002
> 0 KSP Residual norm 8.072272129834e-002
> 0 KSP preconditioned resid norm 8.072272129834e-002 true resid norm
> 5.850358277995e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.535693836801e-009
> 1 KSP preconditioned resid norm 1.535693836801e-009 true resid norm
> 1.378413836547e-002 ||Ae||/||Ax|| 2.356118670085e-001
> 3 SNES Function norm 5.377276379928e-002
> 0 KSP Residual norm 7.265044334812e-002
> 0 KSP preconditioned resid norm 7.265044334812e-002 true resid norm
> 5.377276379928e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 8.196914267894e-009
> 1 KSP preconditioned resid norm 8.196914267894e-009 true resid norm
> 1.643681592299e-002 ||Ae||/||Ax|| 3.056717706448e-001
> 4 SNES Function norm 4.957825627064e-002
> 0 KSP Residual norm 6.538539498475e-002
> 0 KSP preconditioned resid norm 6.538539498475e-002 true resid norm
> 4.957825627064e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.605278143372e-009
> 1 KSP preconditioned resid norm 1.605278143372e-009 true resid norm
> 1.365749144340e-002 ||Ae||/||Ax|| 2.754734125550e-001
> 5 SNES Function norm 4.576573391352e-002
> 0 KSP Residual norm 5.884685187863e-002
> 0 KSP preconditioned resid norm 5.884685187863e-002 true resid norm
> 4.576573391352e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.917790130377e-009
> 1 KSP preconditioned resid norm 3.917790130377e-009 true resid norm
> 2.918137698804e-002 ||Ae||/||Ax|| 6.376250196967e-001
> 6 SNES Function norm 4.224348383506e-002
> 0 KSP Residual norm 5.296216341013e-002
> 0 KSP preconditioned resid norm 5.296216341013e-002 true resid norm
> 4.224348383506e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.384279752582e-009
> 1 KSP preconditioned resid norm 1.384279752582e-009 true resid norm
> 8.645143617596e-003 ||Ae||/||Ax|| 2.046503468168e-001
> 7 SNES Function norm 3.895875122953e-002
> 0 KSP Residual norm 4.766594475257e-002
> 0 KSP preconditioned resid norm 4.766594475257e-002 true resid norm
> 3.895875122953e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 5.442999105246e-009
> 1 KSP preconditioned resid norm 5.442999105246e-009 true resid norm
> 3.199366262059e-002 ||Ae||/||Ax|| 8.212188946227e-001
> 8 SNES Function norm 3.588203219083e-002
> 0 KSP Residual norm 4.289934859308e-002
> 0 KSP preconditioned resid norm 4.289934859308e-002 true resid norm
> 3.588203219083e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 5.069272581944e-009
> 1 KSP preconditioned resid norm 5.069272581944e-009 true resid norm
> 3.315026802067e-002 ||Ae||/||Ax|| 9.238681868510e-001
> 9 SNES Function norm 3.299674865285e-002
> 0 KSP Residual norm 3.860941169595e-002
> 0 KSP preconditioned resid norm 3.860941169595e-002 true resid norm
> 3.299674865285e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 2.314510318621e-009
> 1 KSP preconditioned resid norm 2.314510318621e-009 true resid norm
> 1.422355468145e-002 ||Ae||/||Ax|| 4.310592789335e-001
> 10 SNES Function norm 3.020092421335e-002
> 0 KSP Residual norm 3.457428537321e-002
> 0 KSP preconditioned resid norm 3.457428537321e-002 true resid norm
> 3.020092421335e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.171225245965e-009
> 1 KSP preconditioned resid norm 3.171225245965e-009 true resid norm
> 6.700877909403e-003 ||Ae||/||Ax|| 2.218765843742e-001
> 11 SNES Function norm 2.761432326644e-002
> 0 KSP Residual norm 3.100402216444e-002
> 0 KSP preconditioned resid norm 3.100402216444e-002 true resid norm
> 2.761432326644e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 2.317753799744e-009
> 1 KSP preconditioned resid norm 2.317753799744e-009 true resid norm
> 1.143024510909e-002 ||Ae||/||Ax|| 4.139245057287e-001
> 12 SNES Function norm 2.483228477543e-002
> 0 KSP Residual norm 2.716039584199e-002
> 0 KSP preconditioned resid norm 2.716039584199e-002 true resid norm
> 2.483228477543e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.024860175617e-009
> 1 KSP preconditioned resid norm 1.024860175617e-009 true resid norm
> 5.071961436716e-003 ||Ae||/||Ax|| 2.042486820115e-001
> 13 SNES Function norm 2.155599009420e-002
> 0 KSP Residual norm 2.247739022940e-002
> 0 KSP preconditioned resid norm 2.247739022940e-002 true resid norm
> 2.155599009420e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.231896568498e-009
> 1 KSP preconditioned resid norm 1.231896568498e-009 true resid norm
> 2.253717888475e-003 ||Ae||/||Ax|| 1.045518150002e-001
> 14 SNES Function norm 1.758159262430e-002
> 0 KSP Residual norm 1.640654408633e-002
> 0 KSP preconditioned resid norm 1.640654408633e-002 true resid norm
> 1.758159262430e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.203409491551e-009
> 1 KSP preconditioned resid norm 1.203409491551e-009 true resid norm
> 3.340286893989e-003 ||Ae||/||Ax|| 1.899877312236e-001
> 15 SNES Function norm 1.275874713861e-002
> 0 KSP Residual norm 8.737890404296e-003
> 0 KSP preconditioned resid norm 8.737890404296e-003 true resid norm
> 1.275874713861e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.862616851249e-010
> 1 KSP preconditioned resid norm 3.862616851249e-010 true resid norm
> 9.158071400861e-004 ||Ae||/||Ax|| 7.177876715771e-002
> 16 SNES Function norm 5.367994969686e-003
> 0 KSP Residual norm 1.873266786098e-009
> 0 KSP preconditioned resid norm 1.873266786098e-009 true resid norm
> 5.367994969686e-003 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 9.236612780542e-017
> 1 KSP preconditioned resid norm 9.236612780542e-017 true resid norm
> 4.487656305545e-010 ||Ae||/||Ax|| 8.360023306445e-008
> 17 SNES Function norm 1.843858578272e-008
> 0 KSP Residual norm 3.418191528615e-015
> 0 KSP preconditioned resid norm 3.418191528615e-015 true resid norm
> 1.843858578272e-008 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 2.091028447697e-022
> 1 KSP preconditioned resid norm 2.091028447697e-022 true resid norm
> 9.356082852780e-016 ||Ae||/||Ax|| 5.074186796662e-008
> 18 SNES Function norm 1.582175998776e-008
> STEP 1 (Newton iterations: 18)
>
> 0 SNES Function norm 7.071067811866e-002
> 0 KSP Residual norm 9.965760716669e-002
> 0 KSP preconditioned resid norm 9.965760716669e-002 true resid norm
> 7.071067811866e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 4.158690871520e-009
> 1 KSP preconditioned resid norm 4.158690871520e-009 true resid norm
> 1.356168089543e-002 ||Ae||/||Ax|| 1.917911305090e-001
> 1 SNES Function norm 6.402155946870e-002
> 0 KSP Residual norm 8.969183775926e-002
> 0 KSP preconditioned resid norm 8.969183775926e-002 true resid norm
> 6.402155946870e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 7.922035131300e-009
> 1 KSP preconditioned resid norm 7.922035131300e-009 true resid norm
> 4.173737132742e-002 ||Ae||/||Ax|| 6.519268145573e-001
> 2 SNES Function norm 5.850726192206e-002
> 0 KSP Residual norm 8.072264774465e-002
> 0 KSP preconditioned resid norm 8.072264774465e-002 true resid norm
> 5.850726192206e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 4.356474211542e-009
> 1 KSP preconditioned resid norm 4.356474211542e-009 true resid norm
> 2.083500604436e-002 ||Ae||/||Ax|| 3.561097436437e-001
> 3 SNES Function norm 5.377933295280e-002
> 0 KSP Residual norm 7.265037686612e-002
> 0 KSP preconditioned resid norm 7.265037686612e-002 true resid norm
> 5.377933295280e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 8.772318530630e-009
> 1 KSP preconditioned resid norm 8.772318530630e-009 true resid norm
> 5.284958913103e-002 ||Ae||/||Ax|| 9.827118751623e-001
> 4 SNES Function norm 4.958751191600e-002
> 0 KSP Residual norm 6.538533386375e-002
> 0 KSP preconditioned resid norm 6.538533386375e-002 true resid norm
> 4.958751191600e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.128741903850e-009
> 1 KSP preconditioned resid norm 1.128741903850e-009 true resid norm
> 2.526410501148e-003 ||Ae||/||Ax|| 5.094852319729e-002
> 5 SNES Function norm 4.577729047509e-002
> 0 KSP Residual norm 5.884679667348e-002
> 0 KSP preconditioned resid norm 5.884679667348e-002 true resid norm
> 4.577729047509e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 5.763627011382e-009
> 1 KSP preconditioned resid norm 5.763627011382e-009 true resid norm
> 1.051243252216e-002 ||Ae||/||Ax|| 2.296429608013e-001
> 6 SNES Function norm 4.225677503639e-002
> 0 KSP Residual norm 5.296211439112e-002
> 0 KSP preconditioned resid norm 5.296211439112e-002 true resid norm
> 4.225677503639e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.022912340341e-009
> 1 KSP preconditioned resid norm 1.022912340341e-009 true resid norm
> 3.573383237647e-003 ||Ae||/||Ax|| 8.456355778617e-002
> 7 SNES Function norm 3.897321226706e-002
> 0 KSP Residual norm 4.766590050155e-002
> 0 KSP preconditioned resid norm 4.766590050155e-002 true resid norm
> 3.897321226706e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.528025220977e-009
> 1 KSP preconditioned resid norm 3.528025220977e-009 true resid norm
> 1.960313404416e-002 ||Ae||/||Ax|| 5.029899488355e-001
> 8 SNES Function norm 3.589720610234e-002
> 0 KSP Residual norm 4.289930864255e-002
> 0 KSP preconditioned resid norm 4.289930864255e-002 true resid norm
> 3.589720610234e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 4.133432759880e-009
> 1 KSP preconditioned resid norm 4.133432759880e-009 true resid norm
> 1.940005023620e-002 ||Ae||/||Ax|| 5.404334304149e-001
> 9 SNES Function norm 3.301230929196e-002
> 0 KSP Residual norm 3.860937624684e-002
> 0 KSP preconditioned resid norm 3.860937624684e-002 true resid norm
> 3.301230929196e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 8.211304264406e-010
> 1 KSP preconditioned resid norm 8.211304264406e-010 true resid norm
> 7.328958637952e-003 ||Ae||/||Ax|| 2.220068451781e-001
> 10 SNES Function norm 3.030900587812e-002
> 0 KSP Residual norm 3.474843739750e-002
> 0 KSP preconditioned resid norm 3.474843739750e-002 true resid norm
> 3.030900587812e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.265840938498e-009
> 1 KSP preconditioned resid norm 3.265840938498e-009 true resid norm
> 1.358870142093e-002 ||Ae||/||Ax|| 4.483387371916e-001
> 11 SNES Function norm 2.718409957830e-002
> 0 KSP Residual norm 3.013614572851e-002
> 0 KSP preconditioned resid norm 3.013614572851e-002 true resid norm
> 2.718409957830e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.652744245097e-009
> 1 KSP preconditioned resid norm 1.652744245097e-009 true resid norm
> 1.202105117910e-002 ||Ae||/||Ax|| 4.422089149754e-001
> 12 SNES Function norm 2.437348813670e-002
> 0 KSP Residual norm 2.629377332723e-002
> 0 KSP preconditioned resid norm 2.629377332723e-002 true resid norm
> 2.437348813670e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 3.959255153953e-009
> 1 KSP preconditioned resid norm 3.959255153953e-009 true resid norm
> 2.578989386428e-002 ||Ae||/||Ax|| 1.058112557367e+000
> 13 SNES Function norm 2.199784341474e-002
> 0 KSP Residual norm 2.328182605620e-002
> 0 KSP preconditioned resid norm 2.328182605620e-002 true resid norm
> 2.199784341474e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 8.915626892590e-010
> 1 KSP preconditioned resid norm 8.915626892590e-010 true resid norm
> 6.263373898192e-003 ||Ae||/||Ax|| 2.847267243477e-001
> 14 SNES Function norm 1.833996742657e-002
> 0 KSP Residual norm 1.794186796967e-002
> 0 KSP preconditioned resid norm 1.794186796967e-002 true resid norm
> 1.833996742657e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 1.694980794482e-009
> 1 KSP preconditioned resid norm 1.694980794482e-009 true resid norm
> 2.372076451714e-003 ||Ae||/||Ax|| 1.293391856453e-001
> 15 SNES Function norm 1.384131369872e-002
> 0 KSP Residual norm 1.074320273869e-002
> 0 KSP preconditioned resid norm 1.074320273869e-002 true resid norm
> 1.384131369872e-002 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 7.118408455169e-010
> 1 KSP preconditioned resid norm 7.118408455169e-010 true resid norm
> 4.592913592019e-003 ||Ae||/||Ax|| 3.318264213927e-001
> 16 SNES Function norm 8.126551489387e-003
> 0 KSP Residual norm 2.817712852237e-009
> 0 KSP preconditioned resid norm 2.817712852237e-009 true resid norm
> 8.126551489387e-003 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 2.239560797627e-016
> 1 KSP preconditioned resid norm 2.239560797627e-016 true resid norm
> 1.053395037920e-009 ||Ae||/||Ax|| 1.296238680448e-007
> 17 SNES Function norm 4.871218193429e-008
> 0 KSP Residual norm 1.123675925695e-014
> 0 KSP preconditioned resid norm 1.123675925695e-014 true resid norm
> 4.871218193429e-008 ||Ae||/||Ax|| 1.000000000000e+000
> 1 KSP Residual norm 5.307928330547e-022
> 1 KSP preconditioned resid norm 5.307928330547e-022 true resid norm
> 2.893354456541e-015 ||Ae||/||Ax|| 5.939693813026e-008
> 18 SNES Function norm 5.035279029783e-008
> STEP 2 (Newton iterations: 18)
>
> diverged reason: -6
>
>
> 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>
>>
>>
>
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