add missing header

include/aspect/time_stepping/repeat_on_nonlinear_fail.h

@@ -0,0 +1,102 @@
+/*
+  Copyright (C) 2018 - 2023 by the authors of the ASPECT code.
+
+  This file is part of ASPECT.
+
+  ASPECT 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 2, or (at your option)
+  any later version.
+
+  ASPECT 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 ASPECT; see the file LICENSE.  If not see
+  <http://www.gnu.org/licenses/>.
+*/
+
+
+#ifndef _aspect_time_stepping_repeat_on_nonlinear_fail_h
+#define _aspect_time_stepping_repeat_on_nonlinear_fail_h
+
+#include <aspect/time_stepping/interface.h>
+
+namespace aspect
+{
+  namespace TimeStepping
+  {
+    using namespace dealii;
+
+    /**
+     * A class that implements a time stepping plugin to repeat a time step if the
+     * nonlinear solver failed to converge in the specified number of iterations.
+     * This class is automatically enabled if the user specifies that he/she wants
+     * to do this.
+     *
+     * @ingroup TimeStepping
+     */
+    template <int dim>
+    class RepeatOnNonlinearFail : public Interface<dim>, public SimulatorAccess<dim>
+    {
+      public:
+        /**
+         * Constructor.
+         */
+        RepeatOnNonlinearFail () = default;
+
+        /**
+         * @copydoc aspect::TimeStepping::Interface<dim>::execute()
+         */
+        double
+        execute() override;
+
+        /**
+         * This function notifies the plugin that the nonlinear solver
+         * failed.
+         */
+        void nonlinear_solver_has_failed() const;
+
+        /**
+         * The main execute() function.
+         */
+        std::pair<Reaction, double>
+        determine_reaction(const TimeStepInfo &info) override;
+
+        static
+        void
+        declare_parameters (ParameterHandler &prm);
+
+        void
+        parse_parameters (ParameterHandler &prm) override;
+
+      private:
+        /**
+         * Parameter to determine how much smaller the time step should be
+         * repeated as.
+         */
+        double cut_back_amount = 0.5;
+
+        /**
+         * Enabled by nonlinear_solver_has_failed() to signal that this
+         * plugin needs to act.
+        */
+        mutable bool nonlinear_solver_just_failed = false;
+
+        /**
+         * How many times should we try cutting the timestep size?
+        */
+        unsigned int maximum_number_of_repeats = 10;
+
+        /**
+         * How many times have we been repeating already right now?
+        */
+        unsigned int current_number_of_repeats = 0;
+    };
+  }
+}
+
+
+#endif