On Wed, Dec 1, 2021 at 6:55 PM Jed Brown <[email protected]> wrote: > Matthew Knepley <[email protected]> writes: > > > On Wed, Dec 1, 2021 at 5:17 PM Abhyankar, Shrirang G < > > [email protected]> wrote: > > > >> “You can certainly have many fields on a given edge, but I don't know > >> what it would mean to have two edges since no topological query could > tell > >> the difference.” > >> > >> > >> > >> The two edges in a power grid represent two parallel power lines that > are > >> connected between two locations (vertices). There are line ids (stored > in > >> the component data) to distinguish the two lines. > >> > > > > Yes, so you can tell the difference in the function space (since > difference > > current passes down each one), but _topologically_ you cannot. If you put > > duplicate cells in, then > > some topological queries will give unexpected results, like the join of > the > > two vertices. > > This could be modeled with some ghost vertices. So instead of > > a ------ b > \_____/ > > you would set up > > a ---o---- b > \___o___/ > > Those ghost vertices don't have to "do" anything, but they make the edges > topologically distinct. > > Shri, what problems might this cause? >
Yes, this would work, but it looks like the multiple cells are not causing them problems right now with the questions they are asking the mesh. Matt -- 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/>
