Tempus_StepperExplicit_decl.hpp

Go to the documentation of this file.

//@HEADER
// *****************************************************************************
//          Tempus: Time Integration and Sensitivity Analysis Package
//
// Copyright 2017 NTESS and the Tempus contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
//@HEADER

#ifndef Tempus_StepperExplicit_decl_hpp
#define Tempus_StepperExplicit_decl_hpp

// Tempus
#include "Tempus_config.hpp"
#include "Tempus_Stepper.hpp"

template <class Scalar>
class ExplicitODEParameters {
 public:
  ExplicitODEParameters() : timeStepSize_(Scalar(0.0)), stageNumber_(0) {}

  ExplicitODEParameters(Scalar timeStepSize, int stageNumber = 0)
    : timeStepSize_(timeStepSize), stageNumber_(stageNumber)
  {
  }

  Scalar timeStepSize_;
  int stageNumber_;
};

namespace Tempus {

template <class Scalar>
class StepperExplicit : virtual public Tempus::Stepper<Scalar> {
 public:

  virtual void setModel(
      const Teuchos::RCP<const Thyra::ModelEvaluator<Scalar> >& appModel);

  virtual Teuchos::RCP<const Thyra::ModelEvaluator<Scalar> > getModel() const
  {
    return appModel_;
  }

  virtual Scalar getInitTimeStep(
      const Teuchos::RCP<SolutionHistory<Scalar> >& /* solutionHistory */) const
  {
    return std::numeric_limits<Scalar>::max();
  }

  virtual void setInitialConditions(
      const Teuchos::RCP<SolutionHistory<Scalar> >& solutionHistory);

  virtual void setSolver(
      Teuchos::RCP<Thyra::NonlinearSolverBase<Scalar> > solver);

  virtual Teuchos::RCP<Thyra::NonlinearSolverBase<Scalar> > getSolver() const
  {
    return Teuchos::null;
  }

  //  thus a no-op for explicit steppers.
  virtual void setInitialGuess(
      Teuchos::RCP<const Thyra::VectorBase<Scalar> > /* initial_guess */)
  {
  }

  virtual bool isExplicit() const { return true; }
  virtual bool isImplicit() const { return false; }
  virtual bool isExplicitImplicit() const
  {
    return isExplicit() && isImplicit();
  }
  virtual bool isOneStepMethod() const { return true; }
  virtual bool isMultiStepMethod() const { return !isOneStepMethod(); }

  virtual void evaluateExplicitODE(
      Teuchos::RCP<Thyra::VectorBase<Scalar> > xDot,
      Teuchos::RCP<const Thyra::VectorBase<Scalar> > x, const Scalar time,
      const Teuchos::RCP<ExplicitODEParameters<Scalar> >& p);

  virtual void evaluateExplicitODE(
      Teuchos::RCP<Thyra::VectorBase<Scalar> > xDotDot,
      Teuchos::RCP<const Thyra::VectorBase<Scalar> > x,
      Teuchos::RCP<const Thyra::VectorBase<Scalar> > xDot, const Scalar time,
      const Teuchos::RCP<ExplicitODEParameters<Scalar> >& p);


  virtual void describe(Teuchos::FancyOStream& out,
                        const Teuchos::EVerbosityLevel verbLevel) const;

  virtual bool isValidSetup(Teuchos::FancyOStream& out) const;

  void setStepperExplicitValues(Teuchos::RCP<Teuchos::ParameterList> pl);

 protected:
  Teuchos::RCP<const Thyra::ModelEvaluator<Scalar> > appModel_;

  Thyra::ModelEvaluatorBase::InArgs<Scalar> inArgs_;
  Thyra::ModelEvaluatorBase::OutArgs<Scalar> outArgs_;
};

}  // namespace Tempus
#endif  // Tempus_StepperExplicit_decl_hpp