[petsc-dev] MatMatMult

[Pierre Jolivet]

On Tue, 6 Jun 2017 13:44:06 -0500, Hong wrote:
> Pierre :
>
>> Yes, of course I defined (*C)->ops->matmultnumeric =
>> MatMatMultNumeric_MPIBAIJ_MPIDense in
>> MatMatMultSymbolic_MPIBAIJ_MPIDense.
>> However, the routine MatMatMultSymbolic_MPIBAIJ_MPIDense is never
>> reached when calling MatMatMult with scall == MAT_REUSE_MATRIX
>>
> 
> (http://www.mcs.anl.gov/petsc/petsc-current/src/mat/interface/matrix.c.html#line9487
>> [1], just to be sure I added a dummy printf in
>> MatMatMultSymbolic_MPIBAIJ_MPIDense and nothing is displayed with
>> MAT_REUSE_MATRIX, MAT_INITIAL_MATRIX works as intended)
>
>  MatMatMultSymbolic_xxx() is called only for MAT_INITIAL_MATRIX,
> during which, it defines
> (*C)->ops->matmultnumeric = MatMatMultNumeric_MPIBAIJ_MPIDense;

Sorry, I was not thorough enough. What I meant to say is that I never 
call MatMatMult with MAT_INITIAL_MATRIX, so MatMatMultSymbolic_xxx is 
never called.
Is there another way?
I cannot use MAT_INITIAL_MATRIX because I want to manage the underlying 
memory, and I'm guessing MAT_INITIAL_MATRIX will delete whatever is in C 
and reallocate memory on its own.

Thanks in advance for your help,
Pierre

> Then MatMatMult(A,C,MAT_REUSE_MATRIX,..) calls 
>  (*(*C)->ops->matmultnumeric)(A,B,*C); (line 9432 in matrix.c)
>
> which should go to MatMatMultNumeric_MPIBAIJ_MPIDense.
>
> You may follow a debugging process
> using petsc/src/mat/examples/tests/ex109.c
>
> Are you working on a branch of petsc? If so, I may take a look and
> see what is the problem.
>
> Hong
>
>>>> 2) I'm having trouble when scall == MAT_REUSE_MATRIX. Here,
>>>
>>>
>>>
>>
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/dense/mpi/mpidense.c.html#line1208
>>> [2]
>>>
>>>> [2] it looks that the numeric part of the MatMatMult (which is
>>>> called when scall == MAT_REUSE_MATRIX) is hardwired to this
>>>> routine
>>>
>>>
>>>
>>
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line376
>>> [3]
>>> [3]. 
>>> br>
>>>
>>
> 
> s.anl.gov/petsc/petsc-current/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line556"
>>> rel="noreferrer"
>>>
>>
> 
> target="_blank">http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line556
>>> [2]
>>>
>>>
>>>
>>
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/dense/mpi/mpidense.c.html#line1208
>>> [4]
>>> [3]
>>>
>>>
>>>
>>
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line376
>>> [5]
>
>
>
> Links:
> ------
> [1]
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/interface/matrix.c.html#line9487
> [2]
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/dense/mpi/mpidense.c.html#line1208
> [3]
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line376
> [4]
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/dense/mpi/mpidense.c.html#line1208
> [5]
> 
> http://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line376