Doc update.

git-svn-id: https://svn.dealii.org/trunk@5036 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/examples/step-11/step-11.cc b/deal.II/examples/step-11/step-11.cc
index 9fb341197ea3bae4d1290dd328e83782877e79f8..ff7b1bc82541c90d2d1a1553e9e61f9f5f815872 100644 (file)
--- a/deal.II/examples/step-11/step-11.cc
+++ b/deal.II/examples/step-11/step-11.cc
@@ -306,6 +306,19 @@ void LaplaceProblem<dim>::setup_system ()
                                   // ``SparsityPattern'', which we
                                   // generate by copying from the
                                   // intermediate object.
+                                  //
+                                  // As a further sidenote, you will
+                                  // notice that we do not explicitly
+                                  // have to ``compress'' the
+                                  // sparsity pattern here. This, of
+                                  // course, is due to the fact that
+                                  // the ``copy_from'' function
+                                  // generates a compressed object
+                                  // right from the start, to which
+                                  // you cannot add new entries
+                                  // anymore. The ``compress'' call
+                                  // is therefore implicit in the
+                                  // ``copy_from'' call.
   sparsity_pattern.copy_from (csp);
   system_matrix.reinit (sparsity_pattern);
 };