Thank you, Barry.
If I have two matrix A and B of type MPIBAIJ, how can I get the product of
these two matrix C= AB? When I called the routine MatMatMult(), I got the
following error
MatMatMult not supported for B of type mpibaij!
---- Original message ----
>Date: Thu, 5 Apr 2012 22:13:36 -0500
>From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry Smith <bsmith at
>mcs.anl.gov>)
>Subject: Re: [petsc-users] Questions about PCMG
>To: PETSc users list <petsc-users at mcs.anl.gov>
>
>
>On Apr 5, 2012, at 10:09 PM, Yuqi Wu wrote:
>
>> Thank you, Barry.
>>
>> Now I put in the KSPSetOperators() in the ComputeJacobian() routine. It
>> works. And I found out some interesting things, it also triggers the LU
>> factorization for the fine grid smoothers. Now I get 2 MatLUFactorSym (one
>> for coarse and one the fine grid), and 4 MatLUFactorNum (two for coarse and
>> two for fine) for 2 SNES iteration.
>>
>> Can I also ask another question? Because MatPtAP is not supported for baij
>> matrices. I want to setup a routine to calculate coarse operator if the fine
>> grid matrices is of type baij. Is there any approach so that I can keep the
>> symbolic pattern and only redo the numeric part in each SNES, similar to
>> MatPtAPSymbolic and MatPtAPNumeric?
>
> You call the KSPOperators() with the coarse matrix in each Jacobian
> computation and just use the same coarse matrrix, just put new values into
> the nonzero locations. that is you do not need to create a new coarse matrix
> with matcreate each Jacobian just use the same as before. Call
> MatZeroEntries() before reusing.
>
> Barry
>
>>
>> Best
>>
>> Yuqi
>>
>>
>>
>> ---- Original message ----
>>> Date: Thu, 5 Apr 2012 21:35:58 -0500
>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry Smith <bsmith
>>> at mcs.anl.gov>)
>>> Subject: Re: [petsc-users] Questions about PCMG
>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>
>>>
>>> On Apr 5, 2012, at 9:31 PM, Yuqi Wu wrote:
>>>
>>>> Hi, Barry,
>>>>
>>>> If I use the following routines to setup the coarse operator instead of
>>>> calling PCMGSetGalerkin()
>>>>
>>>> ierr = PCMGGetCoarseSolve(finepc,&ctx->coarseksp);CHKERRQ(ierr);
>>>> ierr = KSPSetOperators(ctx->coarseksp, coarsealgebra->J, coarsealgebra->J,
>>>> DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
>>>
>>> Are you calling this at every SNES iteration? You should call this inside
>>> your ComputeJacobian() function, is that where you call it? Passing the
>>> DIFFERENT_NONZERO_PATTERN will also trigger a new symbolic factorization
>>> also.
>>>
>>> The refactorization fo the find grid smoother not being redone only
>>> effects the fine grid smoother, not the coarse grid.
>>> Barry
>>>
>>>
>>>>
>>>> Then in the case I have 2 SNES iteration, the MatLUFactorSym and
>>>> MatLUFactorNum are only called twice in the program. Is this issue also
>>>> related to the refactorization issue for the fine grid smoother?
>>>>
>>>> Best
>>>>
>>>> Yuqi
>>>>
>>>>
>>>>
>>>> ---- Original message ----
>>>>> Date: Thu, 5 Apr 2012 14:10:02 -0500
>>>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry Smith
>>>>> <bsmith at mcs.anl.gov>)
>>>>> Subject: Re: [petsc-users] Questions about PCMG
>>>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>>>
>>>>>
>>>>> Yes, at least that is the intention.
>>>>>
>>>>> Barry
>>>>>
>>>>> On Apr 5, 2012, at 2:06 PM, Yuqi Wu wrote:
>>>>>
>>>>>> Hi, Barry,
>>>>>>
>>>>>> If my matrix is of type mpibaij, then I cannot use the Galerkin flag in
>>>>>> the PCMG, e.g. PCMGSetGalerkin(finepc,PETSC_TRUE);
>>>>>>
>>>>>> Otherwise, I got the following error messages in PETSc
>>>>>> [0]PETSC ERROR: No support for this operation for this object type!
>>>>>> [0]PETSC ERROR: Matrix of type <mpibaij> does not support PtAP!
>>>>>>
>>>>>> Can I use the following commands to setup the coarse operator
>>>>>>
>>>>>> ierr = PCMGGetCoarseSolve(finepc,&ctx->coarseksp);CHKERRQ(ierr);
>>>>>> ierr = KSPSetOperators(ctx->coarseksp, coarsealgebra->J,
>>>>>> coarsealgebra->J, DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
>>>>>>
>>>>>> Thank you.
>>>>>>
>>>>>> Best
>>>>>>
>>>>>> Yuqi
>>>>>>
>>>>>>
>>>>>> ---- Original message ----
>>>>>>> Date: Thu, 5 Apr 2012 08:10:03 -0500
>>>>>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry Smith
>>>>>>> <bsmith at mcs.anl.gov>)
>>>>>>> Subject: Re: [petsc-users] Questions about PCMG
>>>>>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>>>>>
>>>>>>>
>>>>>>> It looks like the logic for that line has gotten so convoluted that it
>>>>>>> lost its purpose and is not triggering the rebuilding on the finest
>>>>>>> level. Thanks for finding this, we will investigate and get back to you.
>>>>>>>
>>>>>>>
>>>>>>> Barry
>>>>>>>
>>>>>>> If your code is not complicated and you are willing to send it to us at
>>>>>>> petsc-maint at mcs.anl.gov that will make it quicker for us to
>>>>>>> determine the problem.
>>>>>>>
>>>>>>>
>>>>>>> On Apr 4, 2012, at 11:55 PM, Yuqi Wu wrote:
>>>>>>>
>>>>>>>> Thank you Barry.
>>>>>>>>
>>>>>>>> I am using exact LU as subdomain solver, so I find out PCSetUp_LU() in
>>>>>>>> my debugging output. But there are only three PCSetUp_LU() was called
>>>>>>>> in my program. One in the down smoother of the first SNES, one in the
>>>>>>>> coarse solve of the first SNES, and one in the coarse solve of the
>>>>>>>> second SNES.
>>>>>>>>
>>>>>>>> In those PCSetUp_LU(), MatLUFactorSymbolic and MatLUFactorNumeric is
>>>>>>>> called. But I still have no ideas about the actions taken on the down
>>>>>>>> smoother of the second SNES.
>>>>>>>>
>>>>>>>> I try to setup a breakpoint for PCSetUp_MG(). I find out that the IF
>>>>>>>> statement shown in below is called in the first SNES but not the
>>>>>>>> second SNES. Is it has something related to this issue?
>>>>>>>>
>>>>>>>> /* If user did not provide fine grid operators OR operator was not
>>>>>>>> updated since last global KSPSetOperators() */
>>>>>>>> /* so use those from global PC */
>>>>>>>> /* Is this what we always want? What if user wants to keep old one? */
>>>>>>>> ierr =
>>>>>>>> KSPGetOperatorsSet(mglevels[n-1]->smoothd,PETSC_NULL,&opsset);CHKERRQ(ierr);
>>>>>>>> ierr = KSPGetPC(mglevels[0]->smoothd,&cpc);CHKERRQ(ierr);
>>>>>>>> ierr = KSPGetPC(mglevels[n-1]->smoothd,&mpc);CHKERRQ(ierr);
>>>>>>>> if (!opsset || ((cpc->setupcalled == 1) && (mpc->setupcalled == 2)) ||
>>>>>>>> ((mpc == cpc) && (mpc->setupcalled == 2))) {
>>>>>>>> ierr = PetscInfo(pc,"Using outer operators to define finest grid
>>>>>>>> operator \n because
>>>>>>>> PCMGGetSmoother(pc,nlevels-1,&ksp);KSPSetOperators(ksp,...); was not
>>>>>>>> called.\n");CHKERRQ(ierr);
>>>>>>>> ierr =
>>>>>>>> KSPSetOperators(mglevels[n-1]->smoothd,pc->mat,pc->pmat,pc->flag);CHKERRQ(ierr);
>>>>>>>> }
>>>>>>>>
>>>>>>>> Thank you.
>>>>>>>>
>>>>>>>> Yuqi
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> ---- Original message ----
>>>>>>>>> Date: Wed, 4 Apr 2012 19:51:23 -0500
>>>>>>>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry Smith
>>>>>>>>> <bsmith at mcs.anl.gov>)
>>>>>>>>> Subject: Re: [petsc-users] Questions about PCMG
>>>>>>>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Step through the PCSetUp() function using "next" and you will it
>>>>>>>>> first making the decision of whether to continue with the setup or
>>>>>>>>> simply return early.
>>>>>>>>>
>>>>>>>>> When it gets to the lines
>>>>>>>>>
>>>>>>>>> if (pc->ops->setup) {
>>>>>>>>> ierr = (*pc->ops->setup)(pc);CHKERRQ(ierr);
>>>>>>>>> }
>>>>>>>>>
>>>>>>>>> don't use "next" instead use "step" and it will go into the function
>>>>>>>>> PCSetUp_ILU() and you can move through that one with "next"
>>>>>>>>>
>>>>>>>>>> I cannot find any MatLUFactorSymbolic or MatLUFactorNumeric calls in
>>>>>>>>>> the debugger.
>>>>>>>>>
>>>>>>>>> It has to be calling them. Did you use "break MatLUFactorSymbolic" in
>>>>>>>>> the debugger?
>>>>>>>>>
>>>>>>>>> Barry
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On Apr 4, 2012, at 7:45 PM, Yuqi Wu wrote:
>>>>>>>>>
>>>>>>>>>> ---- Original message ----
>>>>>>>>>>> Date: Wed, 4 Apr 2012 13:55:55 -0500
>>>>>>>>>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry Smith
>>>>>>>>>>> <bsmith at mcs.anl.gov>)
>>>>>>>>>>> Subject: Re: [petsc-users] Questions about PCMG
>>>>>>>>>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Note: In most applications the flag SAME_NONZERO_PATTERN is
>>>>>>>>>>> provided in the compute Jacobian routine, this means that the
>>>>>>>>>>> SYMBOLIC factorization needs to be only done ONCE per matrix; only
>>>>>>>>>>> the numeric factorization needs to be done when the nonzero values
>>>>>>>>>>> have changed (the symbolic need not be repeated). Are you using
>>>>>>>>>>> this flag? How many times in the NUMERIC factorization being done?
>>>>>>>>>>>
>>>>>>>>>>> When you run the program with -info it will print information of
>>>>>>>>>>> the form: (run on one process to make life simple)
>>>>>>>>>>>
>>>>>>>>>>> Setting PC with identical preconditioner\
>>>>>>>>>>> Setting up new PC
>>>>>>>>>>> Setting up PC with same nonzero pattern\
>>>>>>>>>>> Setting up PC with different nonzero pattern\n
>>>>>>>>>>>
>>>>>>>>>>> How many, and exactly what messages of this form are you getting?
>>>>>>>>>>>
>>>>>>>>>>> When all else fails you can run the program in the debugger to
>>>>>>>>>>> track what is happening and why.
>>>>>>>>>>>
>>>>>>>>>>> Put a breakpoint in PCSetUp() then each time it gets called use
>>>>>>>>>>> next to step through it to see what is happening.
>>>>>>>>>>>
>>>>>>>>>>> First thing to check, is PCSetUp() getting called on each level for
>>>>>>>>>>> each new SNES iteration?
>>>>>>>>>>>
>>>>>>>>>>> Second thing, if it is then why is it not triggering the new
>>>>>>>>>>> numerical factorization.
>>>>>>>>>>
>>>>>>>>>> I run the program in debugger. I got total 8 PCSetUp() in the
>>>>>>>>>> program. And I believe that PCSetup() is called on each level for
>>>>>>>>>> each new SNES iteration.
>>>>>>>>>>
>>>>>>>>>> But I don't know how to check why is it not triggering the new
>>>>>>>>>> numerical factorization in the debugger. I cannot find any
>>>>>>>>>> MatLUFactorSymbolic or MatLUFactorNumeric calls in the debugger.
>>>>>>>>>> Could you give me some suggestions to find out the problem?
>>>>>>>>>>
>>>>>>>>>> Best
>>>>>>>>>>
>>>>>>>>>> Yuqi
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Barry
>>>>>>>>>>>
>>>>>>>>>>> On Apr 4, 2012, at 1:34 PM, Yuqi Wu wrote:
>>>>>>>>>>>
>>>>>>>>>>>> Thanks, Adam.
>>>>>>>>>>>>
>>>>>>>>>>>> Yes. I am using the Galerkin coarse grids. But I am not sure
>>>>>>>>>>>> whether the coarse grid is not getting refactored in the second
>>>>>>>>>>>> SNES solve or the fine grid smoother is not getting refactored in
>>>>>>>>>>>> the second SNES solve.
>>>>>>>>>>>>
>>>>>>>>>>>> In the -info output attached in the previous email, the fine grid
>>>>>>>>>>>> matrix is of size 11585 by 11585, and the coarse grid matrix is of
>>>>>>>>>>>> size 4186 by 4186. In the -info output, I found out three
>>>>>>>>>>>> MatLUFactorSymbolic_SeqAIJ routines, one for fine martrix, and two
>>>>>>>>>>>> for coarse matrix.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): Reallocs 2 Fill ratio:given 5
>>>>>>>>>>>> needed 11.401
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): Run with -pc_factor_fill 11.401
>>>>>>>>>>>> or use
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): PCFactorSetFill(pc,11.401);
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): for best performance.
>>>>>>>>>>>> [0] Mat_CheckInode_FactorLU(): Found 8057 nodes of 11585. Limit
>>>>>>>>>>>> used: 5. Using Inode routines
>>>>>>>>>>>>
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): Reallocs 1 Fill ratio:given 5
>>>>>>>>>>>> needed 7.07175
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): Run with -pc_factor_fill 7.07175
>>>>>>>>>>>> or use
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): PCFactorSetFill(pc,7.07175);
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): for best performance.
>>>>>>>>>>>> [0] Mat_CheckInode_FactorLU(): Found 1764 nodes of 4186. Limit
>>>>>>>>>>>> used: 5. Using Inode routines
>>>>>>>>>>>>
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): Reallocs 1 Fill ratio:given 5
>>>>>>>>>>>> needed 7.07175
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): Run with -pc_factor_fill 7.07175
>>>>>>>>>>>> or use
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): PCFactorSetFill(pc,7.07175);
>>>>>>>>>>>> [0] MatLUFactorSymbolic_SeqAIJ(): for best performance.
>>>>>>>>>>>> [0] Mat_CheckInode_FactorLU(): Found 1764 nodes of 4186. Limit
>>>>>>>>>>>> used: 5. Using Inode routines
>>>>>>>>>>>>
>>>>>>>>>>>> So I believe that the fine grid smoother is not getting refactored
>>>>>>>>>>>> in the second SNES solve.
>>>>>>>>>>>>
>>>>>>>>>>>> Best
>>>>>>>>>>>>
>>>>>>>>>>>> Yuqi
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> ---- Original message ----
>>>>>>>>>>>>> Date: Wed, 4 Apr 2012 14:24:28 -0400
>>>>>>>>>>>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of "Mark F.
>>>>>>>>>>>>> Adams" <mark.adams at columbia.edu>)
>>>>>>>>>>>>> Subject: Re: [petsc-users] Questions about PCMG
>>>>>>>>>>>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>>>>>>>>>>>
>>>>>>>>>>>>> I would expect 4 calls to MatLUFactorSym here. It looks like the
>>>>>>>>>>>>> coarse grid is not getting refactored in the second SNES solve.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Are you using Galerkin coarse grids? Perhaps you are not setting
>>>>>>>>>>>>> a new coarse grid with KSPSetOperator and so MG does not bother
>>>>>>>>>>>>> refactoring it.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Mark
>>>>>>>>>>>>>
>>>>>>>>>>>>> On Apr 4, 2012, at 1:53 PM, Yuqi Wu wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>>> Thank you.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Can I ask another question?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> In my log summary output, it shows that although there are two
>>>>>>>>>>>>>> SNES iteration and total 9 linear iterations. The functions
>>>>>>>>>>>>>> MatLUFactorSym and MatLUFactorNum are only called for three
>>>>>>>>>>>>>> times.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> MatLUFactorSym 3 1.0 1.4073e+00 1.0 0.00e+00 0.0 0.0e+00
>>>>>>>>>>>>>> 0.0e+00 1.5e+01 1 0 0 0 2 1 0 0 0 2 0
>>>>>>>>>>>>>> MatLUFactorNum 3 1.0 3.2754e+01 1.0 9.16e+09 1.0 0.0e+00
>>>>>>>>>>>>>> 0.0e+00 0.0e+00 31 97 0 0 0 32 97 0 0 0 280
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> I checked the -info output. It shows that One
>>>>>>>>>>>>>> MatLUFactorSymbolic_SeqAIJ() is called in down smoother of the
>>>>>>>>>>>>>> first SNES, one MatLUFactorSymbolic_SeqAIJ() is called in the
>>>>>>>>>>>>>> coarse solve of the first SNES, and one
>>>>>>>>>>>>>> MatLUFactorSymbolic_SeqAIJ() is called in the down smoother of
>>>>>>>>>>>>>> the second SNES.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Do you have any ideas why there are 9 multigrid iterations, but
>>>>>>>>>>>>>> only 3 MatLUFactorSymbolic calls in the program?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Best
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Yuqi
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> ---- Original message ----
>>>>>>>>>>>>>>> Date: Tue, 3 Apr 2012 20:08:27 -0500
>>>>>>>>>>>>>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry
>>>>>>>>>>>>>>> Smith <bsmith at mcs.anl.gov>)
>>>>>>>>>>>>>>> Subject: Re: [petsc-users] Questions about PCMG
>>>>>>>>>>>>>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> There are two linear solves (for 1 SNES and 2 SNES) so there
>>>>>>>>>>>>>>> are two MGSetUp on each level. Then a total of 9 multigrid
>>>>>>>>>>>>>>> iterations (in both linear solves together) hence 9 smoother on
>>>>>>>>>>>>>>> level 0 (level 0 means coarse grid solve). One smooth down and
>>>>>>>>>>>>>>> one smooth up on level 1 hence 18 total smooths on level 1. 9
>>>>>>>>>>>>>>> computation of residual on level 1 and 18 MgInterp because that
>>>>>>>>>>>>>>> logs both the restriction to level 0 and the interpolation back
>>>>>>>>>>>>>>> to level 1 and 18 = 9 + 9.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Barry
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> On Apr 3, 2012, at 7:57 PM, Yuqi Wu wrote:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Hi, Barry,
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Thank you. If my program converges in two SNES iteration,
>>>>>>>>>>>>>>>> 0 SNES norm 1.014991e+02, 0 KSP its (nan coarse its average),
>>>>>>>>>>>>>>>> last norm 0.000000e+00
>>>>>>>>>>>>>>>> 1 SNES norm 9.925218e-05, 4 KSP its (5.25 coarse its average),
>>>>>>>>>>>>>>>> last norm 2.268574e-06.
>>>>>>>>>>>>>>>> 2 SNES norm 1.397282e-09, 5 KSP its (5.20 coarse its average),
>>>>>>>>>>>>>>>> last norm 1.312605e-12.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> And -pc_mg_log shows the following output
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> MGSetup Level 0 2 1.0 3.4091e-01 2.1 0.00e+00 0.0
>>>>>>>>>>>>>>>> 3.0e+02 6.0e+04 3.0e+01 1 0 3 11 2 1 0 3 11 2 0
>>>>>>>>>>>>>>>> MGSmooth Level 0 9 1.0 1.2126e+01 1.0 9.38e+08 3.2
>>>>>>>>>>>>>>>> 2.8e+03 1.7e+03 6.4e+02 33 71 28 3 34 35 71 28 3 35 415
>>>>>>>>>>>>>>>> MGSetup Level 1 2 1.0 1.3925e-01 2.1 0.00e+00 0.0
>>>>>>>>>>>>>>>> 1.5e+02 3.1e+04 2.3e+01 0 0 1 3 1 0 0 1 3 1 0
>>>>>>>>>>>>>>>> MGSmooth Level 1 18 1.0 5.8493e+00 1.0 3.66e+08 3.1
>>>>>>>>>>>>>>>> 1.5e+03 2.9e+03 3.6e+02 16 28 15 3 19 17 28 15 3 19 339
>>>>>>>>>>>>>>>> MGResid Level 1 9 1.0 1.1826e-01 1.4 1.49e+06 2.4
>>>>>>>>>>>>>>>> 2.0e+02 2.7e+03 9.0e+00 0 0 2 0 0 0 0 2 0 0 70
>>>>>>>>>>>>>>>> MGInterp Level 1 18 1.0 1.2317e-01 1.3 7.74e+05 2.2
>>>>>>>>>>>>>>>> 3.8e+02 1.1e+03 1.8e+01 0 0 4 0 1 0 0 4 0 1 37
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> What are the MGSmooth, MGResid, MGInterp represent for?
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Best
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Yuqi
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> ---- Original message ----
>>>>>>>>>>>>>>>>> Date: Tue, 3 Apr 2012 19:19:23 -0500
>>>>>>>>>>>>>>>>> From: petsc-users-bounces at mcs.anl.gov (on behalf of Barry
>>>>>>>>>>>>>>>>> Smith <bsmith at mcs.anl.gov>)
>>>>>>>>>>>>>>>>> Subject: Re: [petsc-users] Questions about PCMG
>>>>>>>>>>>>>>>>> To: PETSc users list <petsc-users at mcs.anl.gov>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> -pc_mg_log doesn't have anything to do with DA or DMMG it is
>>>>>>>>>>>>>>>>> part of the basic PCMG. Are you sure you are calling
>>>>>>>>>>>>>>>>> SNESSetFromOptions()?
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Barry
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> On Apr 3, 2012, at 6:56 PM, Yuqi Wu wrote:
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Hi, Mark,
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Thank you so much for your suggestion.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> The problem 1 is resolved by avoiding calling
>>>>>>>>>>>>>>>>>> PCMGSetNumberSmoothUp.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> But since I am using the unstructured grid in my
>>>>>>>>>>>>>>>>>> application, I didn't use DA or dmmg, so -pc_mg_log didn't
>>>>>>>>>>>>>>>>>> give any level information. I try to run my code using -info
>>>>>>>>>>>>>>>>>> with 1 processor, and I find out some interesting issues.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>
>>>>>>>
>>>>>
>>>
>
