From 08bd06efe2207ee674eec743a6cba81d74c2511f Mon Sep 17 00:00:00 2001 From: wolf Date: Wed, 11 Aug 1999 15:46:35 +0000 Subject: [PATCH] Doc update. git-svn-id: https://svn.dealii.org/trunk@1676 0785d39b-7218-0410-832d-ea1e28bc413d --- deal.II/lac/include/lac/sparse_vanka.h | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/deal.II/lac/include/lac/sparse_vanka.h b/deal.II/lac/include/lac/sparse_vanka.h index 221528ce61..d575bdeb1b 100644 --- a/deal.II/lac/include/lac/sparse_vanka.h +++ b/deal.II/lac/include/lac/sparse_vanka.h @@ -46,10 +46,17 @@ * each degree of freedom, depending for example on the local neighborhood of * the respective node on a computational grid. * - * The right hand side is built up in the same way, i.e. by copying all entries - * that coupled with the one under present consideration, but it is augmented - * by all degrees of freedom coupling with the degrees from the set described - * above (i.e. the DoFs coupling second order to the present one). + * The right hand side is built up in the same way, i.e. by copying + * all entries that coupled with the one under present consideration, + * but it is augmented by all degrees of freedom coupling with the + * degrees from the set described above (i.e. the DoFs coupling second + * order to the present one). The reason for this is, that the local + * problems to be solved shall have Dirichlet boundary conditions on + * the second order coupling DoFs, so we have to take them into + * account but eliminate them before actually solving; this + * elimination is done by the modification of the right hand side, and + * in the end these degrees of freedom do not occur in the matrix and + * solution vector any more at all. * * This local system is solved and the values are updated into the * destination vector. @@ -91,8 +98,7 @@ * whether this might pose some problems in the inversion of the local matrices. * Maybe someone would like to check this. * - * @author Guido Kanschat, 1999 - */ + * @author Guido Kanschat, documentation mostly by Wolfgang Bangerth; 1999 */ template class SparseVanka { -- 2.39.5