hermes_function.h

// This file is part of Hermes2D.
//
// Hermes2D 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 of the License, or
// (at your option) any later version.
//
// Hermes2D 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 Hermes2D.  If not, see <http://www.gnu.org/licenses/>.

#ifndef __H2D_HERMES_FUNCTION_H
#define __H2D_HERMES_FUNCTION_H

#include "compat.h"
#include "ord.h"
#include "exceptions.h"
#include "mixins.h"

namespace Hermes
{
  struct HERMES_API SplineCoeff
  {
    double a, b, c, d;    // four coefficients of a cubic spline.
  };

  template<typename Scalar>
  class HERMES_API Hermes1DFunction : public Hermes::Mixins::Loggable
  {
  public:
    Hermes1DFunction();

    Hermes1DFunction(Scalar value);

    virtual Scalar value(Scalar x) const;

    virtual Hermes::Ord value(Hermes::Ord x) const;

    virtual Scalar derivative(Scalar x) const;

    virtual Hermes::Ord derivative(Hermes::Ord x) const;

    bool is_constant() const;

  protected:
    bool is_const;
    Scalar const_value;
  };

  template<typename Scalar>
  class HERMES_API Hermes2DFunction : public Hermes::Mixins::Loggable
  {
  public:
    Hermes2DFunction();

    Hermes2DFunction(Scalar value);

    virtual Scalar value(Scalar x, Scalar y) const;

    virtual Hermes::Ord value(Hermes::Ord x, Hermes::Ord y) const;

    virtual Scalar derivative_x(Scalar x, Scalar y) const;
    virtual Scalar derivative_y(Scalar x, Scalar y) const;

    virtual Hermes::Ord derivative_x(Hermes::Ord x, Hermes::Ord y) const;
    virtual Hermes::Ord derivative_y(Hermes::Ord x, Hermes::Ord y) const;

    bool is_constant() const;

  protected:
    bool is_const;
    Scalar const_value;
  };

  template<typename Scalar>
  class HERMES_API Hermes3DFunction : public Hermes::Mixins::Loggable
  {
  public:
    Hermes3DFunction();

    Hermes3DFunction(Scalar value);

    virtual Scalar value(Scalar x, Scalar y, Scalar z) const;

    virtual Hermes::Ord value(Hermes::Ord x, Hermes::Ord y, Hermes::Ord z) const;

    virtual Scalar derivative_x(Scalar x, Scalar y, Scalar z) const;
    virtual Scalar derivative_y(Scalar x, Scalar y, Scalar z) const;
    virtual Scalar derivative_z(Scalar x, Scalar y, Scalar z) const;

    virtual Hermes::Ord derivative_x(Hermes::Ord x, Hermes::Ord y, Hermes::Ord z) const;
    virtual Hermes::Ord derivative_y(Hermes::Ord x, Hermes::Ord y, Hermes::Ord z) const;
    virtual Hermes::Ord derivative_z(Hermes::Ord x, Hermes::Ord y, Hermes::Ord z) const;

    bool is_constant() const;

  protected:
    bool is_const;
    Scalar const_value;
  };
}

#endif