step-27: Lower the linear solver tolerance.

This makes the pictures symmetric.

diff --git a/examples/step-27/step-27.cc b/examples/step-27/step-27.cc
index 6f9934284f5c9ca75b5818ef06cf641f5ed0fb10..1f87b2e4fe902291361a01b1ae7fc4c9968bff67 100644 (file)
--- a/examples/step-27/step-27.cc
+++ b/examples/step-27/step-27.cc
@@ -379,7 +379,7 @@ namespace Step27
   void LaplaceProblem<dim>::solve()
   {
     SolverControl solver_control(system_rhs.size(),
-                                 1e-8 * system_rhs.l2_norm());
+                                 1e-12 * system_rhs.l2_norm());
     SolverCG<>    cg(solver_control);
 
     PreconditionSSOR<> preconditioner;