On Wed, Jul 21, 2021 at 2:54 PM Eric Chamberland < [email protected]> wrote:
> Hi Matthew, > > we did it with PetscSFCreateInverseSF ! > > It is working well without overlap, so we can go forward with this and > compute the overlap afterward with DMPlexDistributeOverlap. > > That works. I think you can also do what you want with https://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PetscSF/PetscSFComputeDegreeBegin.html This is how I usually make the 2-sided information, unless I really need the inverse SF. Thanks, Matt > Thanks, > > Eric > > > On 2021-07-20 10:39 p.m., Eric Chamberland wrote: > > > On 2021-07-14 6:42 p.m., Matthew Knepley wrote: > > > Ah, there was a confusion of intent. GlobalToNatural() is for people that > want data transformed back into the original > order. I thought that was what you wanted. If you just want mesh points in > the original order, we give you the > transformation as part of the output of DMPlexDistribute(). The > migrationSF that is output maps the original point to > the distributed point. You run it backwards to get the original ordering. > > Thanks, > > Matt > > Hi, > > that seems to work better! However, if I understand well the migrationSF > is giving information on the originating process where the elements have > been migrated from. > > Is there a PETSc way to either: > > 1) send back the information to the originating process (somewhat > "inverting" the migrationSF) ? So I can retrieve the "partitioning array" > (just like the "part" parameter in ParMETIS_V3_PartMeshKway) on the sender > process. > > or > > 2) Have the pre-migrationSF: I mean I would like to extract the "where are > the elements going to be sent?" (again like "part" parameter) > > If not, I can always build the communication myself... > > Thanks, > > Eric > > > > > -- > Eric Chamberland, ing., M. Ing > Professionnel de recherche > GIREF/Université Laval > (418) 656-2131 poste 41 22 42 > > -- 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 https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>
