Correct bug

source/solvers/cahn_hilliard.cc

@@ -1327,78 +1327,71 @@ void
 CahnHilliard<dim>::output_newton_update_norms(
   const unsigned int display_precision)
 {
-      auto mpi_communicator = triangulation->get_communicator();
-
-      FEValuesExtractors::Scalar phase_order(0);
-      FEValuesExtractors::Scalar chemical_potential(1);
-
-      ComponentMask phase_order_mask = fe->component_mask(phase_order);
-      ComponentMask chemical_potential_mask = fe->component_mask(chemical_potential);
-
-      const std::vector<IndexSet> index_set_phase_order =
-        DoFTools::locally_owned_dofs_per_component(dof_handler, phase_order_mask);
-      const std::vector<IndexSet> index_set_chemical_potential =
-        DoFTools::locally_owned_dofs_per_component(dof_handler, chemical_potential_mask);
-
-      double local_sum = 0.0;
-      double local_max = std::numeric_limits<double>::lowest();
-
-
-          for (auto j = index_set_phase_order[0].begin();
-               j != index_set_phase_order[0].end();
-               j++)
-            {
-              double dof_newton_update = newton_update[*j];
+  auto mpi_communicator = triangulation->get_communicator();
 
-              local_sum += dof_newton_update * dof_newton_update;
+  FEValuesExtractors::Scalar phase_order(0);
+  FEValuesExtractors::Scalar chemical_potential(1);
 
-              local_max = std::max(local_max, dof_newton_update);
-            }
-        
+  ComponentMask phase_order_mask = fe->component_mask(phase_order);
+  ComponentMask chemical_potential_mask =
+    fe->component_mask(chemical_potential);
 
-      double global_phase_order_l2_norm =
-        std::sqrt(Utilities::MPI::sum(local_sum, mpi_communicator));
-      double global_phase_order_linfty_norm =
-        Utilities::MPI::max(local_max, mpi_communicator);
+  const std::vector<IndexSet> index_set_phase_order =
+    DoFTools::locally_owned_dofs_per_component(dof_handler, phase_order_mask);
+  const std::vector<IndexSet> index_set_chemical_potential =
+    DoFTools::locally_owned_dofs_per_component(dof_handler,
+                                               chemical_potential_mask);
 
-      local_sum = 0.0;
-      local_max = std::numeric_limits<double>::lowest();
+  double local_sum = 0.0;
+  double local_max = std::numeric_limits<double>::lowest();
 
-      for (auto j = index_set_chemical_potential[1].begin();
-           j != index_set_chemical_potential[1].end();
-           j++)
-        {
-          double dof_newton_update = newton_update[*j];
 
-          local_sum += dof_newton_update * dof_newton_update;
+  for (auto j = index_set_phase_order[0].begin();
+       j != index_set_phase_order[0].end();
+       j++)
+    {
+      double dof_newton_update = newton_update[*j];
+
+      local_sum += dof_newton_update * dof_newton_update;
 
-          local_max = std::max(local_max, dof_newton_update);
-        }
+      local_max = std::max(local_max, std::abs(dof_newton_update));
+    }
+
+
+  double global_phase_order_l2_norm =
+    std::sqrt(Utilities::MPI::sum(local_sum, mpi_communicator));
+  double global_phase_order_linfty_norm =
+    Utilities::MPI::max(local_max, mpi_communicator);
+
+  local_sum = 0.0;
+  local_max = std::numeric_limits<double>::lowest();
+
+  for (auto j = index_set_chemical_potential[1].begin();
+       j != index_set_chemical_potential[1].end();
+       j++)
+    {
+      double dof_newton_update = newton_update[*j];
+
+      local_sum += dof_newton_update * dof_newton_update;
+
+      local_max = std::max(local_max, std::abs(dof_newton_update));
+    }
 
-      double global_chemical_potential_l2_norm =
-        std::sqrt(Utilities::MPI::sum(local_sum, mpi_communicator));
-      double global_chemical_potential_linfty_norm =
-        Utilities::MPI::max(local_max, mpi_communicator);
-
-      this->pcout << std::setprecision(display_precision)
-                  << "\n\t||du||_L2 = " << std::setw(6)
-                  << newton_update.l2_norm() << std::setw(6)
-                  << "\t||du||_Linfty = "
-                  << std::setprecision(display_precision)
-                  << newton_update.linfty_norm() << std::endl;
-
-      this->pcout << std::setprecision(display_precision)
-                  << "\n\t||dphi||_L2 = " << std::setw(6)
-                  << global_phase_order_l2_norm << std::setw(6)
-                  << "\t||dphi||_Linfty = "
-                  << std::setprecision(display_precision)
-                  << global_phase_order_linfty_norm << std::endl;
-      this->pcout << std::setprecision(display_precision)
-                  << "\t||deta||_L2 = " << std::setw(6) << global_chemical_potential_l2_norm
-                  << std::setw(6) << "\t||deta||_Linfty = "
-                  << std::setprecision(display_precision)
-                  << global_chemical_potential_linfty_norm << std::endl;
-
+  double global_chemical_potential_l2_norm =
+    std::sqrt(Utilities::MPI::sum(local_sum, mpi_communicator));
+  double global_chemical_potential_linfty_norm =
+    Utilities::MPI::max(local_max, mpi_communicator);
+
+  this->pcout << std::setprecision(display_precision)
+              << "\n\t||dphi||_L2 = " << std::setw(6)
+              << global_phase_order_l2_norm << std::setw(6)
+              << "\t||dphi||_Linfty = " << std::setprecision(display_precision)
+              << global_phase_order_linfty_norm << std::endl;
+  this->pcout << std::setprecision(display_precision)
+              << "\t||deta||_L2 = " << std::setw(6)
+              << global_chemical_potential_l2_norm << std::setw(6)
+              << "\t||deta||_Linfty = " << std::setprecision(display_precision)
+              << global_chemical_potential_linfty_norm << std::endl;
 }
 
 template std::pair<Tensor<1, 2>, Tensor<1, 2>>

source/solvers/navier_stokes_base.cc

@@ -2516,7 +2516,7 @@ NavierStokesBase<dim, VectorType, DofsType>::output_newton_update_norms(
 
               local_sum += dof_newton_update * dof_newton_update;
 
-              local_max = std::max(local_max, dof_newton_update);
+              local_max = std::max(local_max, std::abs(dof_newton_update));
             }
         }
 
@@ -2536,7 +2536,7 @@ NavierStokesBase<dim, VectorType, DofsType>::output_newton_update_norms(
 
           local_sum += dof_newton_update * dof_newton_update;
 
-          local_max = std::max(local_max, dof_newton_update);
+          local_max = std::max(local_max, std::abs(dof_newton_update));
         }
 
       double global_pressure_l2_norm =

tests/core/non_linear_test_system_01.h

@@ -130,10 +130,10 @@ class NonLinearProblemTestClass : public PhysicsSolver<Vector<double>>
   output_newton_update_norms(const unsigned int display_precision) override
   {
     deallog << std::setprecision(display_precision)
-                << "\t||dx||_L2 = " << std::setw(6) << newton_update.l2_norm()
-                << std::setw(6)
-                << "\t||dx||_Linfty = " << std::setprecision(display_precision)
-                << newton_update.linfty_norm() << std::endl;
+            << "\t||dx||_L2 = " << std::setw(6) << newton_update.l2_norm()
+            << std::setw(6)
+            << "\t||dx||_Linfty = " << std::setprecision(display_precision)
+            << newton_update.linfty_norm() << std::endl;
   };
   virtual Vector<double> &
   get_present_solution() override

tests/core/vector_problem.cc

@@ -105,7 +105,8 @@ test()
         {
           correction_norm += dummy_solution[*j] * dummy_solution[*j];
 
-          max_correction = std::max(max_correction, dummy_solution[*j]);
+          max_correction =
+            std::max(max_correction, std::abs(dummy_solution[*j]));
         }
     }
 
@@ -120,10 +121,7 @@ test()
     {
       correction_norm += dummy_solution[*j] * dummy_solution[*j];
 
-      if (dummy_solution[*j] > max_correction)
-        {
-          max_correction = dummy_solution[*j];
-        }
+      max_correction = std::max(max_correction, std::abs(dummy_solution[*j]));
     }
 
   deallog << "||p||_L2 : " << std::sqrt(correction_norm) << std::endl;