[newton] Extract privarswitch implementation to separate class

dumux/nonlinear/CMakeLists.txt

@@ -2,5 +2,6 @@ install(FILES
 findscalarroot.hh
 newtonconvergencewriter.hh
 newtonsolver.hh
+primaryvariableswitchadapter.hh
 staggerednewtonconvergencewriter.hh
 DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/dumux/nonlinear)

dumux/nonlinear/newtonsolver.hh

@@ -55,10 +55,32 @@
 
 #include "newtonconvergencewriter.hh"
 #include "newtonvariablesbackend.hh"
+#include "primaryvariableswitchadapter.hh"
 
 namespace Dumux {
 namespace Detail {
 
+// Helper boolean that states if the assembler exports grid variables
+template<class Assembler> using AssemblerGridVariablesType = typename Assembler::GridVariables;
+template<class Assembler>
+inline constexpr bool assemblerExportsGridVariables
+    = Dune::Std::is_detected_v<AssemblerGridVariablesType, Assembler>;
+
+// helper struct to define the variables on which the privarswitch should operate
+template<class Assembler, bool exportsGridVars = assemblerExportsGridVariables<Assembler>>
+struct PriVarSwitchVariablesType { using Type = typename Assembler::GridVariables; };
+
+// if assembler does not export them, use an empty class. These situations either mean
+// that there is no privarswitch, or, it is handled by a derived implementation.
+template<class Assembler>
+struct PriVarSwitchVariablesType<Assembler, false>
+{ using Type = struct EmptyGridVariables {}; };
+
+// Helper alias to deduce the variables types used in the privarswitch adapter
+template<class Assembler>
+using PriVarSwitchVariables
+    = typename PriVarSwitchVariablesType<Assembler, assemblerExportsGridVariables<Assembler>>::Type;
+
 //! helper struct detecting if an assembler supports partial reassembly
 struct supportsPartialReassembly
 {
@@ -69,13 +91,6 @@ struct supportsPartialReassembly
     {}
 };
 
-//! helper aliases to extract a primary variable switch from the VolumeVariables (if defined, yields int otherwise)
-template<class Assembler>
-using DetectPVSwitch = typename Assembler::GridVariables::VolumeVariables::PrimaryVariableSwitch;
-
-template<class Assembler>
-using GetPVSwitch = Dune::Std::detected_or<int, DetectPVSwitch, Assembler>;
-
 // helper struct and function detecting if the linear solver features a norm() function
 template <class LinearSolver, class Residual>
 using NormDetector = decltype(std::declval<LinearSolver>().norm(std::declval<Residual>()));
@@ -188,10 +203,14 @@ private:
     using ConvergenceWriter = ConvergenceWriterInterface<SolutionVector>;
     using TimeLoop = TimeLoopBase<Scalar>;
 
-    using PrimaryVariableSwitch = typename Detail::GetPVSwitch<Assembler>::type;
-    using HasPriVarsSwitch = typename Detail::GetPVSwitch<Assembler>::value_t; // std::true_type or std::false_type
-    static constexpr bool hasPriVarsSwitch() { return HasPriVarsSwitch::value; };
+    // enable models with primary variable switch
+    // TODO: Always use ParentType::Variables once we require assemblers to export variables
     static constexpr bool assemblerExportsVariables = Impl::exportsVariables<Assembler>;
+    using PriVarSwitchVariables
+        = std::conditional_t<assemblerExportsVariables,
+                             typename ParentType::Variables,
+                             Detail::PriVarSwitchVariables<Assembler>>;
+    using PrimaryVariableSwitchAdapter = Dumux::PrimaryVariableSwitchAdapter<PriVarSwitchVariables>;
 
 public:
     using typename ParentType::Variables;
@@ -208,6 +227,7 @@ public:
     , endIterMsgStream_(std::ostringstream::out)
     , comm_(comm)
     , paramGroup_(paramGroup)
+    , priVarSwitchAdapter_(std::make_unique<PrimaryVariableSwitchAdapter>(paramGroup))
     {
         initParams_(paramGroup);
 
@@ -221,12 +241,6 @@ public:
         // initialize the partial reassembler
         if (enablePartialReassembly_)
             partialReassembler_ = std::make_unique<Reassembler>(this->assembler());
-
-        if (hasPriVarsSwitch())
-        {
-            const int priVarSwitchVerbosity = getParamFromGroup<int>(paramGroup, "PrimaryVariableSwitch.Verbosity", 1);
-            priVarSwitch_ = std::make_unique<PrimaryVariableSwitch>(priVarSwitchVerbosity);
-        }
     }
 
     //! the communicator for parallel runs
@@ -370,13 +384,23 @@ public:
     virtual void newtonBegin(Variables& initVars)
     {
         numSteps_ = 0;
-        initPriVarSwitch_(initVars, HasPriVarsSwitch{});
+
+        if constexpr (hasPriVarsSwitch<PriVarSwitchVariables>)
+        {
+            if constexpr (assemblerExportsVariables)
+                priVarSwitchAdapter_->initialize(Backend::getDofVector(initVars), initVars);
+            else // this assumes assembly with solution (i.e. Variables=SolutionVector)
+                priVarSwitchAdapter_->initialize(initVars, this->assembler().gridVariables());
+        }
+
         const auto& initSol = Backend::getDofVector(initVars);
 
         // write the initial residual if a convergence writer was set
         if (convergenceWriter_)
         {
             this->assembler().assembleResidual(initVars);
+
+            // dummy vector, there is no delta before solving the linear system
             auto delta = Backend::makeZeroDofVector(Backend::size(initSol));
             convergenceWriter_->write(initSol, delta, this->assembler().residual());
         }
@@ -591,7 +615,13 @@ public:
     virtual void newtonEndStep(Variables &vars,
                                const SolutionVector &uLastIter)
     {
-        invokePriVarSwitch_(vars, HasPriVarsSwitch{});
+        if constexpr (hasPriVarsSwitch<PriVarSwitchVariables>)
+        {
+            if constexpr (assemblerExportsVariables)
+                priVarSwitchAdapter_->invoke(Backend::getDofVector(vars), vars);
+            else // this assumes assembly with solution (i.e. Variables=SolutionVector)
+                priVarSwitchAdapter_->invoke(vars, this->assembler().gridVariables());
+        }
 
         ++numSteps_;
 
@@ -633,7 +663,7 @@ public:
     {
         // in case the model has a priVar switch and some some primary variables
         // actually switched their state in the last iteration, enforce another iteration
-        if (priVarsSwitchedInLastIteration_)
+        if (priVarSwitchAdapter_->switched())
             return false;
 
         if (enableShiftCriterion_ && !enableResidualCriterion_)
@@ -854,87 +884,6 @@ protected:
     bool enableResidualCriterion() const
     { return enableResidualCriterion_; }
 
-    /*!
-     * \brief Initialize the privar switch, noop if there is no priVarSwitch
-     */
-    void initPriVarSwitch_(Variables&, std::false_type) {}
-
-    /*!
-     * \brief Initialize the privar switch
-     */
-    void initPriVarSwitch_(Variables& vars, std::true_type)
-    {
-        priVarSwitch_->reset(Backend::size(Backend::getDofVector(vars)));
-        priVarsSwitchedInLastIteration_ = false;
-
-        const auto& problem = this->assembler().problem();
-        const auto& gridGeometry = this->assembler().gridGeometry();
-
-        // if the assembler does not export the variables type
-        // we assume old-style assemblers which operate on solution
-        // vectors and return the grid variables
-        if constexpr (!assemblerExportsVariables)
-            priVarSwitch_->updateDirichletConstraints(problem, gridGeometry,
-                                                      this->assembler().gridVariables(),
-                                                      vars);
-        else
-            priVarSwitch_->updateDirichletConstraints(problem, gridGeometry, vars, Backend::getDofVector(vars));
-    }
-
-    /*!
-     * \brief Switch primary variables if necessary, noop if there is no priVarSwitch
-     */
-    void invokePriVarSwitch_(Variables&, std::false_type) {}
-
-    /*!
-     * \brief Switch primary variables if necessary
-     */
-    void invokePriVarSwitch_(Variables& vars, std::true_type)
-    {
-        // update the variable switch (returns true if the pri vars at at least one dof were switched)
-        // for disabled grid variable caching
-        const auto& gridGeometry = this->assembler().gridGeometry();
-        const auto& problem = this->assembler().problem();
-
-        // we assume an old-style assembler if it doesn't export the Variable type
-        if constexpr (!assemblerExportsVariables)
-        {
-            auto& gridVariables = this->assembler().gridVariables();
-
-            // invoke the primary variable switch
-            priVarsSwitchedInLastIteration_ = priVarSwitch_->update(vars, gridVariables, problem, gridGeometry);
-
-            if (priVarsSwitchedInLastIteration_)
-            {
-                for (const auto& element : elements(gridGeometry.gridView()))
-                {
-                    // if the volume variables are cached globally, we need to update those where the primary variables have been switched
-                    priVarSwitch_->updateSwitchedVolVars(problem, element, gridGeometry, gridVariables, Backend::getDofVector(vars));
-
-                    // if the flux variables are cached globally, we need to update those where the primary variables have been switched
-                    priVarSwitch_->updateSwitchedFluxVarsCache(problem, element, gridGeometry, gridVariables, Backend::getDofVector(vars));
-                }
-            }
-        }
-        else
-        {
-            // invoke the primary variable switch
-            priVarsSwitchedInLastIteration_ = priVarSwitch_->update(Backend::getDofVector(vars), vars, problem, gridGeometry);
-
-            if (priVarsSwitchedInLastIteration_)
-            {
-                for (const auto& element : elements(gridGeometry.gridView()))
-                {
-                    // if the volume variables are cached globally, we need to update those where the primary variables have been switched
-                    priVarSwitch_->updateSwitchedVolVars(problem, element, gridGeometry, vars, Backend::getDofVector(vars));
-
-                    // if the flux variables are cached globally, we need to update those where the primary variables have been switched
-                    priVarSwitch_->updateSwitchedFluxVarsCache(problem, element, gridGeometry, vars, Backend::getDofVector(vars));
-                }
-            }
-        }
-    }
-
     //! optimal number of iterations we want to achieve
     int targetSteps_;
     //! minimum number of iterations we do
@@ -1395,9 +1344,7 @@ private:
     std::size_t numLinearSolverBreakdowns_ = 0; //! total number of linear solves that failed
 
     //! the class handling the primary variable switch
-    std::unique_ptr<PrimaryVariableSwitch> priVarSwitch_;
-    //! if we switched primary variables in the last iteration
-    bool priVarsSwitchedInLastIteration_ = false;
+    std::unique_ptr<PrimaryVariableSwitchAdapter> priVarSwitchAdapter_;
 
     //! convergence writer
     std::shared_ptr<ConvergenceWriter> convergenceWriter_ = nullptr;

dumux/nonlinear/primaryvariableswitchadapter.hh

+// -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+// vi: set et ts=4 sw=4 sts=4:
+/****************************************************************************
+ *   See the file COPYING for full copying permissions.                      *
+ *                                                                           *
+ *   This program is free software: you can redistribute it and/or modify    *
+ *   it under the terms of the GNU General Public License as published by    *
+ *   the Free Software Foundation, either version 3 of the License, or       *
+ *   (at your option) any later version.                                     *
+ *                                                                           *
+ *   This program is distributed in the hope that it will be useful,         *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of          *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the            *
+ *   GNU General Public License for more details.                            *
+ *                                                                           *
+ *   You should have received a copy of the GNU General Public License       *
+ *   along with this program.  If not, see <http://www.gnu.org/licenses/>.   *
+ *****************************************************************************/
+/*!
+ * \file
+ * \ingroup Nonlinear
+ * \brief An adapter for the Newton to manage models with primary variable switch
+ */
+#ifndef DUMUX_NONLINEAR_PRIMARY_VARIABLE_SWITCH_ADAPTER_HH
+#define DUMUX_NONLINEAR_PRIMARY_VARIABLE_SWITCH_ADAPTER_HH
+
+#include <memory>
+#include <dune/common/std/type_traits.hh>
+
+namespace Dumux {
+namespace Detail {
+
+//! helper aliases to extract a primary variable switch from the VolumeVariables (if defined, yields int otherwise)
+template<class Variables>
+using DetectPVSwitch = typename Variables::VolumeVariables::PrimaryVariableSwitch;
+
+template<class Variables>
+using GetPVSwitch = Dune::Std::detected_or<int, DetectPVSwitch, Variables>;
+
+template<class Variables>
+using PrimaryVariableSwitch = typename GetPVSwitch<Variables>::type;
+
+} // end namespace Detail
+
+/*!
+ * \ingroup Nonlinear
+ * \brief Helper boolean to check if the given variables involve primary variable switching.
+ */
+template<class Variables>
+inline constexpr bool hasPriVarsSwitch = typename Detail::GetPVSwitch<Variables>::value_t();
+
+/*!
+ * \ingroup Nonlinear
+ * \brief An adapter for the Newton to manage models with primary variable switch
+ */
+template <class Variables, bool isValid = hasPriVarsSwitch<Variables>>
+class PrimaryVariableSwitchAdapter
+{
+    using PrimaryVariableSwitch = typename Detail::PrimaryVariableSwitch<Variables>;
+
+public:
+    PrimaryVariableSwitchAdapter(const std::string& paramGroup = "")
+    {
+        const int priVarSwitchVerbosity = getParamFromGroup<int>(paramGroup, "PrimaryVariableSwitch.Verbosity", 1);
+        priVarSwitch_ = std::make_unique<PrimaryVariableSwitch>(priVarSwitchVerbosity);
+    }
+
+    /*!
+     * \brief Initialize the privar switch
+     */
+    template<class SolutionVector>
+    void initialize(SolutionVector& sol, Variables& vars)
+    {
+        priVarSwitch_->reset(sol.size());
+        priVarsSwitchedInLastIteration_ = false;
+        const auto& problem = vars.curGridVolVars().problem();
+        const auto& gridGeometry = problem.gridGeometry();
+        priVarSwitch_->updateDirichletConstraints(problem, gridGeometry, vars, sol);
+    }
+
+    /*!
+     * \brief Switch primary variables if necessary
+     */
+    template<class SolutionVector>
+    void invoke(SolutionVector& uCurrentIter, Variables& vars)
+    {
+        // update the variable switch (returns true if the pri vars at at least one dof were switched)
+        // for disabled grid variable caching
+        const auto& problem = vars.curGridVolVars().problem();
+        const auto& gridGeometry = problem.gridGeometry();
+
+        // invoke the primary variable switch
+        priVarsSwitchedInLastIteration_ = priVarSwitch_->update(uCurrentIter, vars, problem, gridGeometry);
+        if (priVarsSwitchedInLastIteration_)
+        {
+            for (const auto& element : elements(gridGeometry.gridView()))
+            {
+                // if the volume variables are cached globally, we need to update those where the primary variables have been switched
+                priVarSwitch_->updateSwitchedVolVars(problem, element, gridGeometry, vars, uCurrentIter);
+
+                // if the flux variables are cached globally, we need to update those where the primary variables have been switched
+                priVarSwitch_->updateSwitchedFluxVarsCache(problem, element, gridGeometry, vars, uCurrentIter);
+            }
+        }
+    }
+
+    /*!
+     * \brief Whether the primary variables have been switched in the last call to invoke
+     */
+    bool switched() const
+    { return priVarsSwitchedInLastIteration_; }
+
+private:
+    //! the class handling the primary variable switch
+    std::unique_ptr<PrimaryVariableSwitch> priVarSwitch_;
+    //! if we switched primary variables in the last iteration
+    bool priVarsSwitchedInLastIteration_ = false;
+};
+
+/*!
+ * \ingroup Nonlinear
+ * \brief An empty adapter for the Newton for models without primary variable switch
+ */
+template <class Variables>
+class PrimaryVariableSwitchAdapter<Variables, false>
+{
+public:
+    PrimaryVariableSwitchAdapter(const std::string& paramGroup = "") {}
+
+    template<class SolutionVector>
+    void initialize(SolutionVector&, Variables&) {}
+
+    template<class SolutionVector>
+    void invoke(SolutionVector&, Variables&) {}
+
+    bool switched() const { return false; }
+};
+
+} // end namespace Dumux
+
+#endif