On Wed, May 31, 2023 at 6:37 PM Ferrand, Jesus A. <ferra...@my.erau.edu> wrote:
> Dear PETSc team: > > For one of my applications, I need to know which owned DAG points in a > (DMPlex) are other ranks' ghosts. > Say, rank-0 has some point "x" (which it owns) and it shows up in, say, > rank-1 as a ghost numbered "y". > Then, if I inspect the "Point" PestcSF, in rank-1 there should be a leaf > for "y" that records rank-0 and the value of "x", right? > However, back in rank-0, the same PetscSF has no record that "x" is "y" in > rank-1 (and potentially "z","a","b",... in additional ranks). > > Is this what, in PetscSF terminology, is referred to as "One-Sided"? > > If so, I think what I am really asking is how can I obtain a "Two-Sided" > version of the PointSF? > You need https://petsc.org/main/manualpages/PetscSF/PetscSFComputeDegreeBegin/ If the point is not in the leaf list (owned) and has rootdegree > 1 (shared), it is your point. Thanks, Matt > Sincerely: > > *J.A. Ferrand* > > Embry-Riddle Aeronautical University - Daytona Beach - FL > Ph.D. Candidate, Aerospace Engineering > > M.Sc. Aerospace Engineering > > B.Sc. Aerospace Engineering > > B.Sc. Computational Mathematics > > > *Phone:* (386)-843-1829 > > *Email(s):* ferra...@my.erau.edu > > jesus.ferr...@gmail.com > -- 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/>
