[deal.II] deal.II Newsletter #227
Hello everyone! This is deal.II newsletter #227. It automatically reports recently merged features and discussions about the deal.II finite element library. ## Below you find a list of recently proposed or merged features: #14321: Rotate for dim=1 spacedim=2 (proposed by peterrum) https://github.com/dealii/dealii/pull/14321 #14320: CGAL: use dealii's constexpr Utilities::pow instead of std::pow (proposed by tamiko; merged) https://github.com/dealii/dealii/pull/14320 #14318: Versions for weight_fe_q_dofs_by_entity/compute_weights_fe_q_dofs_by_entity with Q4 storage (proposed by peterrum) https://github.com/dealii/dealii/pull/14318 #14317: Create compute_weights_fe_q_dofs_by_entity() (proposed by peterrum) https://github.com/dealii/dealii/pull/14317 #14316: Add TensorProductMatrixCreator namespace (proposed by peterrum) https://github.com/dealii/dealii/pull/14316 #14315: FEEvaluation::submit_xxx(): Create some local copies to reduce potential aliasing (proposed by kronbichler) https://github.com/dealii/dealii/pull/14315 #14314: Reduce organizational overhead/pointer chasing in FEEvaluation/read (proposed by kronbichler) https://github.com/dealii/dealii/pull/14314 #14313: Do not dereference cend (proposed by dangars; merged) https://github.com/dealii/dealii/pull/14313 #14312: Restructure includes of FloatingPointComparator (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14312 #14311: Simplify code in DoFInfo::read_dof_indices (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14311 #14310: Add shortcut to detect whether a DoF is constrained (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14310 #14309: Fix exponential complexity of FloatingPointComparator with nesting (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14309 #14308: CGAL: fix warnings and fix compilation with cgal 5.5 (proposed by tamiko; merged) https://github.com/dealii/dealii/pull/14308 #14307: Use FloatingPointComparator in TriangulationDescription (proposed by peterrum; merged) https://github.com/dealii/dealii/pull/14307 #14306: Add missing header file (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14306 #14305: GridTools::MarchingCubeAlgorithm: add 1d implementation (proposed by mschreter) https://github.com/dealii/dealii/pull/14305 #14304: Remove SparsityPatternBase, for now. (proposed by drwells) https://github.com/dealii/dealii/pull/14304 #14303: Increase precision of time written in xdmf output (proposed by sebproell; merged) https://github.com/dealii/dealii/pull/14303 #14302: Clean up weight_fe_q_dofs_by_entity (proposed by peterrum; merged) https://github.com/dealii/dealii/pull/14302 #14301: Do not mention update_cell_dof_indices_cache in documentation (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14301 #14300: Do not default initialize projection matrix in GMRES (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14300 #14299: Remove reference to update_cell_dof_indices_cache (proposed by kronbichler; merged) https://github.com/dealii/dealii/pull/14299 #14298: Use FloatingPointComparator in TensorProductMatrixSymmetricSumCollection (proposed by peterrum; merged) https://github.com/dealii/dealii/pull/14298 #14297: TensorProductMatrixSymmetricSumCollection: store matrices/vectors flat (proposed by peterrum; merged) https://github.com/dealii/dealii/pull/14297 #14296: Rename FPArrayComparator -> FloatingPointComparator (proposed by peterrum; merged) https://github.com/dealii/dealii/pull/14296 #14246: Improve error message. (proposed by bangerth; merged) https://github.com/dealii/dealii/pull/14246 #14234: Normal flux constraints: map DoF indices to vector DoF indices (proposed by zjiaqi2018; merged) https://github.com/dealii/dealii/pull/14234 ## And this is a list of recently opened or closed discussions: #14319: Compilation failure on the tester when compiling with clang (cgal 5.2.2) (opened and closed) https://github.com/dealii/dealii/issues/14319 #13411: Setup of MatrixFree got slower since release 9.3 (closed) https://github.com/dealii/dealii/issues/13411 A list of all major changes since the last release can be found at https://www.dealii.org/developer/doxygen/deal.II/recent_changes.html. Thanks for being part of the community! Let us know about questions, problems, bugs or just share your experience by writing to dealii@googlegroups.com, or by opening issues or pull requests at https://www.github.com/dealii/dealii. Additional information can be found at https://www.dealii.org/. -- 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
Re: [deal.II] Mechanisms for deleting cells/edges/vertices in some region
On 9/26/22 10:04, Lucas Myers wrote: I'm trying to construct a rectangular grid with features at arbitrary locations. The most straightforward way of doing this that I can think of is to generate a rectangular hypercube, delete the cells/edges/vertices around feature locations, and then attach other triangulations (e.g. a hyper_cube_with_cylindrical_hole) at the vacant locations. Is there a simple-ish utility for removing parts of the domain in this way? And does the process differ for a distributed triangulation? I've been perusing the documentation for Triangulation, GridTools, and GridGenerator and haven't been able to find anything. There are functions in namespace GridGenerator that (i) create a mesh from another one by removing individual cells, and (ii) create a mesh from two or more other ones by merging them. I forgot the name of the former, the latter is called GridGenerator::merge_triangulation(). Best W. -- Wolfgang Bangerth email: bange...@colostate.edu www: http://www.math.colostate.edu/~bangerth/ -- 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/c9b1f52f-31a5-6c5d-a005-8f8282c5c32e%40colostate.edu.
Re: [deal.II] How to read all the dof elements in a cell in Petsc MPI problem
On 9/27/22 23:50, Rahul Gopalan Ramachandran wrote: Thank you for the clarification. Isend should be the way to patch this. Alternatively, what is your opinion on copying the matrix to a single processor (if that is possible) using MPI_Gather? Would the cell iterators then no longer work? Ignoring scalability will this also be an option? At least in principle, of course, we'd like to avoid writing programs that we know can't scale because each process stores data replicated everywhere -- like the entire matrix. In practice, if your goal is to run on 10 or 20 processes, this may still work, though you should recognize that the system matrix is the largest object you probably have in your program (even if you fully distribute it). If your goal is to replicate the matrix on every process, it might be easiest to create a data structure that collects all of the local contributions (local matrix, plus the dof indices array) and send that around between processes, which then all build their own matrix. That may be simpler than sending around the matrix because the latter is a PETSc object to which you don't easily have access to its internal representation. Best W. -- Wolfgang Bangerth email: bange...@colostate.edu www: http://www.math.colostate.edu/~bangerth/ -- 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/eb258ba9-a221-5229-17e5-61453b639cf6%40colostate.edu.
