From: Marc Fehling Date: Sun, 13 Dec 2020 06:33:52 +0000 (-0700) Subject: Added GridTools::get_subdomain_association() for CellId collections. X-Git-Tag: v9.3.0-rc1~552^2 X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F11366%2Fhead;p=dealii.git Added GridTools::get_subdomain_association() for CellId collections. --- diff --git a/doc/news/changes/minor/20210107Fehling b/doc/news/changes/minor/20210107Fehling new file mode 100644 index 0000000000..03b702a819 --- /dev/null +++ b/doc/news/changes/minor/20210107Fehling @@ -0,0 +1,5 @@ +New: Function GridTools::get_subdomain_association() determines +the owning process of any valid cell on a Triangulation that is +represented by a globally unique CellId. +
+(Marc Fehling, 2021/01/07) diff --git a/include/deal.II/grid/grid_tools.h b/include/deal.II/grid/grid_tools.h index ae933ff775..93698a6c0f 100644 --- a/include/deal.II/grid/grid_tools.h +++ b/include/deal.II/grid/grid_tools.h @@ -2100,6 +2100,18 @@ namespace GridTools void partition_multigrid_levels(Triangulation &triangulation); + /** + * This function allows to ask for the owning subdomain of cells identified by + * CellId objects that do not have to exist on the current process. + * + * @note This function has not been implemented yet for + * parallel::fullydistributed::Triangulation. + */ + template + std::vector + get_subdomain_association(const Triangulation &triangulation, + const std::vector & cell_ids); + /** * For each active cell, return in the output array to which subdomain (as * given by the cell->subdomain_id() function) it belongs. The @@ -2135,7 +2147,6 @@ namespace GridTools const Triangulation &triangulation, const types::subdomain_id subdomain); - /** * For a triangulation, return a mask that represents which of its vertices * are "owned" by the current process in the same way as we talk about diff --git a/source/grid/grid_tools.cc b/source/grid/grid_tools.cc index a4fdbb3c0c..b81947d623 100644 --- a/source/grid/grid_tools.cc +++ b/source/grid/grid_tools.cc @@ -18,6 +18,8 @@ #include #include +#include +#include #include #include @@ -3035,6 +3037,101 @@ namespace GridTools } + + template + std::vector + get_subdomain_association(const Triangulation &triangulation, + const std::vector & cell_ids) + { + std::vector subdomain_ids; + subdomain_ids.reserve(cell_ids.size()); + + if (dynamic_cast< + const parallel::fullydistributed::Triangulation *>( + &triangulation) != nullptr) + { + Assert(false, ExcNotImplemented()); + } + else if (const parallel::distributed::Triangulation + *parallel_tria = dynamic_cast< + const parallel::distributed::Triangulation *>( + &triangulation)) + { +#ifndef DEAL_II_WITH_P4EST + Assert( + false, + ExcMessage( + "You are attempting to use a functionality that is only available " + "if deal.II was configured to use p4est, but cmake did not find a " + "valid p4est library.")); +#else + // for parallel distributed triangulations, we will ask the p4est oracle + // about the global partitioning of active cells since this information + // is stored on every process + for (const auto &cell_id : cell_ids) + { + // find descendent from coarse quadrant + typename dealii::internal::p4est::types::quadrant p4est_cell, + p4est_children[GeometryInfo::max_children_per_cell]; + + dealii::internal::p4est::init_coarse_quadrant(p4est_cell); + for (const auto &child_index : cell_id.get_child_indices()) + { + dealii::internal::p4est::init_quadrant_children( + p4est_cell, p4est_children); + p4est_cell = + p4est_children[static_cast(child_index)]; + } + + // find owning process, i.e., the subdomain id + const int owner = + dealii::internal::p4est::functions::comm_find_owner( + const_cast::forest + *>(parallel_tria->get_p4est()), + cell_id.get_coarse_cell_id(), + &p4est_cell, + Utilities::MPI::this_mpi_process( + parallel_tria->get_communicator())); + + Assert(owner >= 0, ExcMessage("p4est should know the owner.")); + + subdomain_ids.push_back(owner); + } +#endif + } + else if (const parallel::shared::Triangulation *shared_tria = + dynamic_cast + *>(&triangulation)) + { + // for parallel shared triangulations, we need to access true subdomain + // ids which are also valid for artificial cells + const std::vector &true_subdomain_ids_of_cells = + shared_tria->get_true_subdomain_ids_of_cells(); + + for (const auto &cell_id : cell_ids) + { + const unsigned int active_cell_index = + shared_tria->create_cell_iterator(cell_id)->active_cell_index(); + subdomain_ids.push_back( + true_subdomain_ids_of_cells[active_cell_index]); + } + } + else + { + // the most general type of triangulation is the serial one. here, all + // subdomain information is directly available + for (const auto &cell_id : cell_ids) + { + subdomain_ids.push_back( + triangulation.create_cell_iterator(cell_id)->subdomain_id()); + } + } + + return subdomain_ids; + } + + + template void get_subdomain_association(const Triangulation &triangulation, diff --git a/source/grid/grid_tools.inst.in b/source/grid/grid_tools.inst.in index 701a0444f6..4c42a33e84 100644 --- a/source/grid/grid_tools.inst.in +++ b/source/grid/grid_tools.inst.in @@ -316,6 +316,13 @@ for (deal_II_dimension : DIMENSIONS; deal_II_space_dimension : SPACE_DIMENSIONS) partition_multigrid_levels( Triangulation &); +# if deal_II_dimension >= 2 + template std::vector + get_subdomain_association( + const Triangulation &, + const std::vector &); +# endif + template void get_subdomain_association( const Triangulation &, diff --git a/tests/grid/grid_tools_subdomain_association_01.cc b/tests/grid/grid_tools_subdomain_association_01.cc new file mode 100644 index 0000000000..3d69e3da0a --- /dev/null +++ b/tests/grid/grid_tools_subdomain_association_01.cc @@ -0,0 +1,141 @@ +// --------------------------------------------------------------------- +// +// Copyright (C) 2020 by the deal.II authors +// +// This file is part of the deal.II library. +// +// The deal.II library is free software; you can use it, redistribute +// it, and/or modify it under the terms of the GNU Lesser General +// Public License as published by the Free Software Foundation; either +// version 2.1 of the License, or (at your option) any later version. +// The full text of the license can be found in the file LICENSE.md at +// the top level directory of deal.II. +// +// --------------------------------------------------------------------- + + +// check GridTools::get_subdomain_association + + +#include + +#include +#include +#include + +#include +#include +#include + +#include +#include + +#include "../tests.h" + +#include "../test_grids.h" + + +enum Type +{ + Shared, + Distributed +}; + + +template +std::unique_ptr> +create_triangulation(Type type) +{ + if (type == Type::Shared) + return std::make_unique>( + MPI_COMM_WORLD, Triangulation::none, true); + else if (type == Type::Distributed) + return std::make_unique>( + MPI_COMM_WORLD); + else + return nullptr; +} + + +template +void +test(parallel::Triangulation &tria) +{ + // ----- setup ----- + tria.clear(); + TestGrids::hyper_line(tria, 4); + + // refine the last cell + for (const auto &cell : tria.active_cell_iterators()) + if (cell->id().to_string() == "0_0:") + cell->set_refine_flag(); + tria.execute_coarsening_and_refinement(); + + // ----- test ----- + // gather global cellid objects + std::vector global_cell_ids; + global_cell_ids.reserve(tria.n_global_active_cells()); + { + std::vector local_cell_ids; + local_cell_ids.reserve(tria.n_active_cells()); + for (const auto &cell : tria.active_cell_iterators()) + if (cell->is_locally_owned()) + local_cell_ids.push_back(cell->id()); + + std::vector> cell_ids_per_processor = + Utilities::MPI::all_gather(MPI_COMM_WORLD, local_cell_ids); + + for (const auto &cell_ids : cell_ids_per_processor) + global_cell_ids.insert(global_cell_ids.end(), + cell_ids.cbegin(), + cell_ids.cend()); + } + + // determine subdomain of every cellid + std::vector subdomain_ids = + GridTools::get_subdomain_association(tria, global_cell_ids); + + // ----- verify results ----- + AssertDimension(tria.n_global_active_cells(), global_cell_ids.size()); + AssertDimension(tria.n_global_active_cells(), subdomain_ids.size()); + + // check if processor owns represented cells that have been assigned to them + for (unsigned int i = 0; i < tria.n_global_active_cells(); ++i) + if (tria.locally_owned_subdomain() == subdomain_ids[i]) + { + const auto cell = tria.create_cell_iterator(global_cell_ids[i]); + Assert(cell->is_locally_owned(), ExcInternalError()); + } + + // check if all processors have the same list of subdomain ids + { + std::vector> subdomain_ids_per_processor = + Utilities::MPI::gather(MPI_COMM_WORLD, subdomain_ids); + + if (tria.locally_owned_subdomain() == 0) + for (unsigned int i = 1; i < subdomain_ids_per_processor.size(); ++i) + Assert(subdomain_ids_per_processor[0] == subdomain_ids_per_processor[i], + ExcInternalError()); + } + + deallog << "OK" << std::endl; +} + + +int +main(int argc, char *argv[]) +{ + Utilities::MPI::MPI_InitFinalize mpi_initialization(argc, argv, 1); + MPILogInitAll log; + + + for (const auto &type : {Type::Shared, Type::Distributed}) + { + deallog.push("2d"); + test(*create_triangulation<2>(type)); + deallog.pop(); + deallog.push("3d"); + test(*create_triangulation<3>(type)); + deallog.pop(); + } +} diff --git a/tests/grid/grid_tools_subdomain_association_01.with_p4est=true.mpirun=4.output b/tests/grid/grid_tools_subdomain_association_01.with_p4est=true.mpirun=4.output new file mode 100644 index 0000000000..e7df6f3440 --- /dev/null +++ b/tests/grid/grid_tools_subdomain_association_01.with_p4est=true.mpirun=4.output @@ -0,0 +1,23 @@ + +DEAL:0:2d::OK +DEAL:0:3d::OK +DEAL:0:2d::OK +DEAL:0:3d::OK + +DEAL:1:2d::OK +DEAL:1:3d::OK +DEAL:1:2d::OK +DEAL:1:3d::OK + + +DEAL:2:2d::OK +DEAL:2:3d::OK +DEAL:2:2d::OK +DEAL:2:3d::OK + + +DEAL:3:2d::OK +DEAL:3:3d::OK +DEAL:3:2d::OK +DEAL:3:3d::OK +