Ack, I realize the pasted screenshot of the relevant equation has disappeared! I've included it as an attachment to this reply.
- Lucas On Saturday, April 22, 2023 at 2:49:07 PM UTC-5 Lucas Myers wrote: > Hi folks, > > I'd like to coarse-grain a finite element field, where the coarse-graining > procedure is just convolving the field with a Gaussian function. More > concretely, I'd like to do the following: > > > For a regular Triangulation, we can calculate <X> at every quadrature > point by iterating through the entire Triangulation and calculating the > integrand at all of the quadrature points. In fact, because there is a > Gaussian in distance in the integrand, we only have to look at cells a > distance ~3a_0 away. > > However, for a distributed triangulation it could be the case that cells > 3a_0 away may be on a different MPI process. My first question is: is there > a way to extend the number of ghost cells along the boundary such that they > are some total distance away from the locally-owned cells on the edge of > the domain? And if not, is there a nice utility to allow me to access > neighboring cells on other domains (albeit, at the cost of some MPI > messages)? > > Otherwise, is there a good way to do this? My guess would be to do all of > the local integrations first, and make a vector of cells which end up > butting against the boundary. Then one could use the `ghost_owners` > function to send information about the edge cells to the adjacent > subdomains, which would then send information back. However that seems a > little in the weeds of using MPI and also would require some error-prone > bookkeeping, which I would like to avoid if possible. > > Thanks so much for any help! > - Lucas > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to dealii+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/b926c832-7bcb-422b-bb78-83d286d328d7n%40googlegroups.com.
