From: wolf Date: Tue, 3 May 2005 18:28:30 +0000 (+0000) Subject: Add some documentation. X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b62071d86444ed3eaeefc613652354c7863be0ed;p=dealii-svn.git Add some documentation. git-svn-id: https://svn.dealii.org/trunk@10629 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/deal.II/include/numerics/matrices.h b/deal.II/deal.II/include/numerics/matrices.h index 863155177f..255d1e2e48 100644 --- a/deal.II/deal.II/include/numerics/matrices.h +++ b/deal.II/deal.II/include/numerics/matrices.h @@ -842,8 +842,29 @@ class MatrixTools : public MatrixCreator const bool eliminate_columns = true); /** - * Same function, but for parallel PETSc - * matrices. + * Same function, but for + * parallel PETSc matrices. Note + * that this function only + * operates on the local range of + * the parallel matrix, i.e. it + * only eliminates rows + * corresponding to degrees of + * freedom for which the row is + * stored on the present + * processor. All other boundary + * nodes are ignored, and it + * doesn't matter whether they + * are present in the first + * argument to this function or + * not. A consequence of this, + * however, is that this function + * has to be called from all + * processors that participate in + * sharing the contents of the + * given matrices and vectors. It + * is also implied that the local + * range for all objects passed + * to this function is the same. */ static void apply_boundary_values (const std::map &boundary_values,