From 9e12329501e3c6c0dea9df9ffe2cbaf250dc5471 Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Sat, 12 Aug 2017 18:22:23 -0600 Subject: [PATCH] Update documentation. --- include/deal.II/dofs/dof_accessor.templates.h | 19 ++++++++--------- include/deal.II/hp/dof_handler.h | 21 ++++++++++++------- 2 files changed, 23 insertions(+), 17 deletions(-) diff --git a/include/deal.II/dofs/dof_accessor.templates.h b/include/deal.II/dofs/dof_accessor.templates.h index b7c55d4eee..881af450ac 100644 --- a/include/deal.II/dofs/dof_accessor.templates.h +++ b/include/deal.II/dofs/dof_accessor.templates.h @@ -3781,16 +3781,15 @@ DoFCellAccessor::set_active_fe_index (const uns "children because no degrees of freedom will be assigned " "to this cell.")); - if (i != DoFHandlerType::default_fe_index) - Assert ((dynamic_cast*> - (this->dof_handler) != nullptr) - || - this->is_locally_owned(), - ExcMessage ("You can only set active_fe_index information on cells " - "that are locally owned. On ghost cells, this information " - "will automatically be propagated from the owning process " - "of that cell, and there is no information at all on " - "artificial cells.")); + Assert ((dynamic_cast*> + (this->dof_handler) != nullptr) + || + this->is_locally_owned(), + ExcMessage ("You can only set active_fe_index information on cells " + "that are locally owned. On ghost cells, this information " + "will automatically be propagated from the owning process " + "of that cell, and there is no information at all on " + "artificial cells.")); dealii::internal::DoFCellAccessor::Implementation::set_active_fe_index (*this, i); } diff --git a/include/deal.II/hp/dof_handler.h b/include/deal.II/hp/dof_handler.h index a00afc782f..a34a838058 100644 --- a/include/deal.II/hp/dof_handler.h +++ b/include/deal.II/hp/dof_handler.h @@ -132,19 +132,26 @@ namespace hp * * When this class is used with either a parallel::shared::Triangulation * or a parallel::distributed::Triangulation, you can only set active - * FE indices on cells that are locally owned or that are ghost cells, + * FE indices on cells that are locally owned, * using a call such as cell-@>set_active_fe_index(...). - * On the other hand, setting the active FE index on artificial cells - * is not allowed. + * On the other hand, setting the active FE index on ghost + * or artificial cells is not allowed. * - * However, setting the index on ghost cells has no real effect: whenever + * Ghost cells do acquire the information what element + * is active on them, however: whenever * you call hp::DoFHandler::distribute_dofs(), all processors that * participate in the parallel mesh exchange information in such a way * that the active FE index on ghost cells equals the active FE index * that was set on that processor that owned that particular ghost cell. - * In other words, information that may have previously been set on - * ghost cells is overwritten so that the active FE index there is - * consistent with the value on the processor that owns the cell. + * Consequently, one can query the @p active_fe_index on ghost + * cells, just not set it by hand. + * + * On artificial cells, no information is available about the + * @p active_fe_index used there. That's because we don't even know + * whether these cells exist at all, and even if they did, the + * current processor does not know anything specific about them. + * See @ref GlossArtificialCell "the glossary entry on artificial cells" + * for more information. * * * @ingroup dofs -- 2.39.5