From: bangerth Date: Fri, 31 Oct 2008 17:22:58 +0000 (+0000) Subject: Improve documentation. There's too much cruft in here, and it all reads like it was... X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6b15613ff7fc392046ea8d41af3c8d520b9199d4;p=dealii-svn.git Improve documentation. There's too much cruft in here, and it all reads like it was written by a German native speaker... git-svn-id: https://svn.dealii.org/trunk@17428 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/deal.II/include/dofs/dof_renumbering.h b/deal.II/deal.II/include/dofs/dof_renumbering.h index 8a11c1f62c..2ec7ab09d6 100644 --- a/deal.II/deal.II/include/dofs/dof_renumbering.h +++ b/deal.II/deal.II/include/dofs/dof_renumbering.h @@ -32,25 +32,25 @@ DEAL_II_NAMESPACE_OPEN * * Within this class, the Cuthill-McKee algorithm is implemented. It * starts at a degree of freedom, searches the other DoFs for those - * which are couple with the one we started with and numbers these in + * which are coupled with the one we started with and numbers these in * a certain way. It then finds the second level of DoFs, namely those * that couple with those of the previous level (which were those that * coupled with the initial DoF) and numbers these. And so on. For the * details of the algorithm, especially the numbering within each - * level, we refer the reader to the book of Schwarz (H.R.Schwarz: - * Methode der finiten Elemente). The reverse Cuthill-McKee algorithm + * level, please see H. R. Schwarz: + * "Methode der finiten Elemente". The reverse Cuthill-McKee algorithm * does the same job, but numbers all elements in the reverse order. * - * These algorithms have one major drawback: they require a good - * starting point, i.e. the degree of freedom index afterwards to be - * numbered zero. This can thus be given by the user, e.g. by - * exploiting knowledge of the actual topology of the domain. It is - * also possible to give several starting indices, which may be used - * to simulate a simple upstream numbering (by giving the inflow dofs - * as starting values) or to make preconditioning faster (by letting - * the dirichlet boundary indices be starting points). + * These algorithms have one major drawback: they require a good starting + * point, i.e. the degree of freedom index that will get a new index of + * zero. The renumbering functions therefore allow the caller to specify such + * an initial DoF, e.g. by exploiting knowledge of the actual topology of the + * domain. It is also possible to give several starting indices, which may be + * used to simulate a simple upstream numbering (by giving the inflow dofs as + * starting values) or to make preconditioning faster (by letting the + * Dirichlet boundary indices be starting points). * - * If no starting index is given, one is chosen by the program, namely + * If no starting index is given, one is chosen automatically, namely * one with the smallest coordination number (the coordination number * is the number of other dofs this dof couples with). This dof is * usually located on the boundary of the domain. There is, however, @@ -71,15 +71,6 @@ DEAL_II_NAMESPACE_OPEN * published in 1984), but certainly not with those used in this * library, featuring several 10,000 to a few 100,000 elements. * - * On the other hand, the need to reduce the bandwidth has decreased - * since with the mentioned number of cells, only iterative solution - * methods are able to solve the resulting matrix systems. These, - * however, are not so demanding with respect to the bandwidth as - * direct solvers used for smaller problems. Things like upstream - * numbering become much more important in recent times, so the - * suboptimality of the renumbering algorithms is not that important - * any more. - * * *

Implementation of renumbering schemes

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