From 43453baae2a2a26c07c3676a07ce234af2d513ab Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Sat, 4 Nov 2017 08:46:45 -0600 Subject: [PATCH] Minor doc update to GridRenumbering::Cuthill_McKee. --- include/deal.II/dofs/dof_renumbering.h | 30 +++++++++++++++----------- 1 file changed, 17 insertions(+), 13 deletions(-) diff --git a/include/deal.II/dofs/dof_renumbering.h b/include/deal.II/dofs/dof_renumbering.h index f7f7694f12..c61617cbc4 100644 --- a/include/deal.II/dofs/dof_renumbering.h +++ b/include/deal.II/dofs/dof_renumbering.h @@ -521,24 +521,28 @@ namespace DoFRenumbering * If the given DoFHandler uses a distributed triangulation (i.e., if * dof_handler.locally_owned() is not the complete index set), the * renumbering is performed on each processor's degrees of freedom - * individually, without any communication between processors. + * individually, without any communication between processors. In other + * words, the resulting renumbering is an attempt at minimizing the bandwidth + * of each diagonal block of the matrix corresponding to one processor + * separately, without making an attempt at minimizing the bandwidth of + * the global matrix. * * @param dof_handler The DoFHandler or hp::DoFHandler object to work on. * @param reversed_numbering Whether to use the original Cuthill-McKee - * algorithm, or to reverse the ordering. + * algorithm, or to reverse the ordering. * @param use_constraints Whether or not to use hanging node constraints in - * determining the reordering of degrees of freedom. + * determining the reordering of degrees of freedom. * @param starting_indices A set of degrees of freedom that form the first - * level of renumbered degrees of freedom. If the set is empty, then a - * single starting entry is chosen automatically among those that have the - * smallest number of others that couple with it. If the DoFHandler is built - * on a parallel triangulation, then on every processor, these starting - * indices need to be a (possibly empty) subset of the - * @ref GlossLocallyOwnedDof "locally owned degrees of freedom". - * These will then be used as starting indices for the local renumbering on - * the current processor. (In other words, this argument will in fact be - * different on every processor unless you pass an empty list as is the - * default.) + * level of renumbered degrees of freedom. If the set is empty, then a + * single starting entry is chosen automatically among those that have the + * smallest number of others that couple with it. If the DoFHandler is built + * on a parallel triangulation, then on every processor, these starting + * indices need to be a (possibly empty) subset of the + * @ref GlossLocallyOwnedDof "locally owned degrees of freedom". + * These will then be used as starting indices for the local renumbering on + * the current processor. (In other words, you will have to choose this + * argument differently on every processor, unless of course you pass an + * empty list as is the default.) */ template void -- 2.39.5