Great. I'll give it try. Thanks Barry.
On 10 December 2010 15:08, Barry Smith <bsmith at mcs.anl.gov> wrote:
>
> ?Dave,
>
> ? I started work last night on this and found the same problem.
>
> ? But I have a solution that I implemented. It seems to work, so far only
> tested with MPICH. You can pull, then run configure, make as usual with MPICH
> (or you can try other MPIs). Note that the PETSc Matlab interface has not
> changed, the PETSC_COMM_SELF is put in automatically for you.
>
> ? Barry
>
> On Dec 10, 2010, at 6:47 AM, Dave May wrote:
>
>> Hey Barry,
>> ?Looking through the docs associated with loadlibrary, calllib etc.,
>> it wasn't obvious to me how to ?extract a global variable
>> (PETSC_COMM_SELF) from a c library.
>>
>> One possible solution may be to write a function
>> ?PetscErrorCode PetscGetCommSelf(MPI_Comm *comm)
>> which simply sets *comm = PETSC_COMM_SELF. If this function was part
>> of libpetsc, then it could be accessed using calllib. Since it's a
>> trivial getter which possibly doesn't belong in the libpetsc, it could
>> be wrapped up with a standalone mex function. Does anyone know a
>> better way?
>>
>> Am I missing something obvious related to how to pull out COMM_SELF from
>> petsc?
>>
>> Cheers,
>> ?Dave
>>
>>
>> On 9 December 2010 23:04, Barry Smith <bsmith at mcs.anl.gov> wrote:
>>>
>>> On Dec 9, 2010, at 3:52 PM, Dave May wrote:
>>>
>>>> Ok, after digging a little bit more, I realise I can configure the pc
>>>> in a command line like
>>>> manner using this syntax '-pc_type','lu'.
>>>>
>>>> What I was hoping to use was ML and hypre, however it appears neither
>>>> of these libraries can be built with --with-mpi=0, which seems to be a
>>>> requirement when calling petsc from matlab.
>>>> Is there a straight forward way to enable hypre and ml to be used when
>>>> --with-mpi=0?
>>>
>>> No. I won't recommend monkeying with that.
>>>
>>> A much better way to do it would be to "improve" the Matlab interface to
>>> support running under MPI; first step of course just sequential (one
>>> process MPI).
>>>
>>> This would be done by putting a PETSC_COMM_SELF field into PetscObject as a
>>> nonconstant property and then have PetscInitalize.m pull the
>>> PETSC_COMM_SELF up from C and put it into PetscObject. Then calls to, for
>>> example, KSPCreate() from Matlab would automatically pass that property in
>>> (currently they just pass 0 in, which works for MPI Uni).
>>>
>>> ? Barry
>>>
>>>>
>>>> Cheers,
>>>> ?Dave
>>>>
>>>>
>>>>
>>>>
>>>> On 9 December 2010 22:26, Dave May <dave.mayhem23 at gmail.com> wrote:
>>>>> Hi Barry,
>>>>> ?Is it possible that you could possible add PetscPC.m?
>>>>> I work with a bunch of matlab users solving Stokes on staggered grid who
>>>>> rely on umfpack. I'd love to be able to get them to try ML or hypre via
>>>>> PETSc.
>>>>>
>>>>> Cheers,
>>>>> ?Dave
>>>>>
>>>
>>>
>
>
