[petsc-users] Using PETSc solvers and preconditioners with mfem

[Julian Andrej]

We tried a similar approach to get MFEM objects to PETSc and the real
problem is that all other convenient functions like creating
gridfunctions and projections, you have to convert them every time
which is basically nothing more than a bad workaround. Stefano Zampini
replied to the issue on github and was stating that there is some
intention to get MFEM working with PETSc but there is no specific
timeframe.

Regards
Julian Andrej

On Tue, Oct 25, 2016 at 6:30 PM, Abdullah Ali Sivas
<abdullahasivas at gmail.com> wrote:
> I will check that. I am preallocating but it may be that I am not allocating
> big enough. I still have to figure out nuance differences between these
> formats to solve the bugs. I appreciate your answer and hope Satish knows
> it.
>
> Thank you,
> Abdullah Ali Sivas
>
>
> On 2016-10-25 12:15 PM, Matthew Knepley wrote:
>
> On Tue, Oct 25, 2016 at 10:54 AM, Abdullah Ali Sivas
> <abdullahasivas at gmail.com> wrote:
>>
>> Hello,
>>
>> I want to use PETSc with mfem and I know that mfem people will figure out
>> a way to do it in few months. But for now as a temporary solution I just
>> thought of converting hypre PARCSR matrices (that is what mfem uses as
>> linear solver package) into PETSc MPIAIJ matrices and I have a semi-working
>> code with some bugs. Also my code is dauntingly slow and seems like not
>> scaling. I have used MatHYPRE_IJMatrixCopy from myhp.c of PETSc and
>> hypre_ParCSRMatrixPrintIJ from par_csr_matrix.c of hypre as starting points.
>> Before starting I checked whether there was anything done similar to this, I
>> could not find anything.
>>
>> My question is, are you aware of such a conversion code (i.e. something
>> like hypre_ParCSRtoPETScMPIAIJ( hypre_ParCSRMatrix *matrix, Mat *A)?
>
> No, but maybe Satish knows. Slow running times most likely come from lack of
> preallocation for the target matrix.
>
>   Thanks,
>
>      Matt
>>
>> Thanks in advance,
>> Abdullah Ali Sivas
>
>
>
>
> --
> What most experimenters take for granted before they begin their experiments
> is infinitely more interesting than any results to which their experiments
> lead.
> -- Norbert Wiener
>
>