From: bangerth Date: Sun, 7 Nov 2010 20:29:18 +0000 (+0000) Subject: Couple more lines. X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a8052644754211dc1f823622da73816b539c4f61;p=dealii-svn.git Couple more lines. git-svn-id: https://svn.dealii.org/trunk@22625 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/examples/step-40/step-40.cc b/deal.II/examples/step-40/step-40.cc index 6b563e88ce..f0283eb776 100644 --- a/deal.II/examples/step-40/step-40.cc +++ b/deal.II/examples/step-40/step-40.cc @@ -239,12 +239,30 @@ LaplaceProblem::~LaplaceProblem () // since it goes to the heart of what // distinguishes %parallel step-40 from // sequential step-6. + // + // At the top we do what we always do: tell + // the DoFHandler object to distribute + // degrees of freedom. Since the + // triangulation we use here is distributed, + // the DoFHandler object is smart enough to + // recognize that on each processor it can + // only distribute degrees of freedom on + // cells it owns; this is followed by an + // exchange step in which processors tell + // each other about degrees of freedom on + // ghost cell. The result is a DoFHandler + // that knows about the degrees of freedom on + // locally owned cells and ghost cells + // (i.e. cells adjacent to locally owned + // cells) but nothing about cells that are + // further away, consistent with the basic + // philosophy of distributed computing that + // no processor can know everything. template void LaplaceProblem::setup_system () { dof_handler.distribute_dofs (fe); - // eliminate locally_owned_dofs = dof_handler.locally_owned_dofs (); DoFTools::extract_locally_relevant_dofs (dof_handler, locally_relevant_dofs);