From 66e65667938b26fbcbdda06de87f1b337b8c973c Mon Sep 17 00:00:00 2001 From: bangerth Date: Sat, 20 Sep 2008 23:31:21 +0000 Subject: [PATCH] Mention Trilinos. git-svn-id: https://svn.dealii.org/trunk@16873 0785d39b-7218-0410-832d-ea1e28bc413d --- deal.II/examples/step-31/doc/intro.dox | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/deal.II/examples/step-31/doc/intro.dox b/deal.II/examples/step-31/doc/intro.dox index 2efef78757..068e63a36a 100644 --- a/deal.II/examples/step-31/doc/intro.dox +++ b/deal.II/examples/step-31/doc/intro.dox @@ -802,6 +802,8 @@ the Stokes matrix.

Implementation details

+

Using different DoFHandler objects

+ One of the things worth explaining up front about the program below is the use of two different DoFHandler objects. If one looks at the structure of the equations above and the scheme for their solution, one realizes that there is @@ -915,6 +917,29 @@ multigrid have been removed. +

Using Trilinos

+ +In much the same way as we used PETSc to support our linear algebra needs in +@ref step_17 "step-17" and @ref step_18 "step-18", we use interfaces to the Trilinos library (see @ref +SoftwareTrilinos) in this program. Trilinos is a very large collection of +everything that has to do with linear and nonlinear algebra, as well as all +sorts of tools around that (and looks like it will grow in many other +directions in the future as well). + +The main reason for using Trilinos, similar to our exploring PETSc, is that it +is a very powerful library that provides a lot more tools than deal.II's own +linear algebra library. That includes, in particular, the ability to work in +parallel on a cluster, using MPI, and a wider variety of preconditioners. In +the latter class, one of the most interesting capabilities is the existence of +the Trilinos ML package that implements an Algebraic Multigrid (AMG) +method. We will use this preconditioner to precondition the second order +operator part of the momentum equation. The ability to solve problems in +parallel will be explored in @ref step_32 "step-32", using the same problem as +discussed here. + + +

The testcase

The case we want to solve here is as follows: we solve the Boussinesq -- 2.39.5