From d31959b0d3c1dd297309439393e106ab66457544 Mon Sep 17 00:00:00 2001 From: bangerth Date: Wed, 23 Jan 2008 16:33:08 +0000 Subject: [PATCH] Document the special case of the constraint x_i=0. git-svn-id: https://svn.dealii.org/trunk@15648 0785d39b-7218-0410-832d-ea1e28bc413d --- .../deal.II/include/dofs/dof_constraints.h | 20 +++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/deal.II/deal.II/include/dofs/dof_constraints.h b/deal.II/deal.II/include/dofs/dof_constraints.h index 09abfb5796..0cf61059ee 100644 --- a/deal.II/deal.II/include/dofs/dof_constraints.h +++ b/deal.II/deal.II/include/dofs/dof_constraints.h @@ -2,7 +2,7 @@ // $Id$ // Version: $Name$ // -// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 by the deal.II authors +// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by the deal.II authors // // This file is subject to QPL and may not be distributed // without copyright and license information. Please refer @@ -48,13 +48,17 @@ class BlockIndices; * * @image html hp-refinement-simple.png * - * there are three constraints: first $x_2=\frac 12 x_0 + \frac 12 x_1$, then - * $x_4=\frac 14 x_0 + \frac 34 x_1$, and finally the identity $x_3=x_1$. All - * three constraints fit the form given above. Similar constraints occur as - * hanging nodes even if all used finite elements are identical. While they - * are most frequent for hanging nodes, constraints of the given form appear - * also in other contexts, see for example the application the @ref step_11 - * "step-11" tutorial program. + * there are three constraints: first $x_2=\frac 12 x_0 + \frac 12 + * x_1$, then $x_4=\frac 14 x_0 + \frac 34 x_1$, and finally the + * identity $x_3=x_1$. All three constraints fit the form given + * above. Similar constraints occur as hanging nodes even if all used + * finite elements are identical. While they are most frequent for + * hanging nodes, constraints of the given form appear also in other + * contexts, see for example the application the @ref step_11 + * "step-11" tutorial program. A special case also covered by the + * current class is the constraint $x_i=0$ although this constraint on + * linear systems is better and more efficiently handled by the + * MatrixTools::apply_boundary_values function. * * The algorithms used in the implementation of this class are described in * some detail in the @ref hp_paper "hp paper". -- 2.39.5