stepper_def.hpp

Go to the documentation of this file.

 
#ifndef ROOT_STEPPER_DEF_HPP
#define ROOT_STEPPER_DEF_HPP
 
#include <Eigen/Dense>
#include <functional>
 
template <typename T>
class StepperBase {
  protected:
    std::function<double(double)> function;  
    bool aitken_requirement;                 
    virtual Eigen::Vector2d compute_step(Eigen::Vector2d) = 0;
    Eigen::Vector2d aitken_step(Eigen::Vector2d previous_iter);
 
  public:
    StepperBase(std::function<double(double)> fun, bool aitken_mode);
    virtual ~StepperBase() = default;
    Eigen::Vector2d step(Eigen::Vector2d previous_step);
};
 
template <typename T>
class NewtonRaphsonStepper : public StepperBase<T> {
  private:
    std::function<double(double)> derivative;  
 
  public:
    NewtonRaphsonStepper(std::function<double(double)> fun, bool aitken_mode, std::function<double(double)> der);
    Eigen::Vector2d compute_step(Eigen::Vector2d previous_iteration) override;
};
 
template <typename T>
class FixedPointStepper : public StepperBase<T> {
  private:
    std::function<double(double)> fixed_point_function;  
 
  public:
    FixedPointStepper(std::function<double(double)> fun, bool aitken_mode, std::function<double(double)> g_fun);
    Eigen::Vector2d compute_step(Eigen::Vector2d previous_iteration) override;
};
 
template <typename T>
class ChordsStepper : public StepperBase<T> {
  private:
    double iter_minus_1, iter_zero;  
    // It could seem a bit redundant because the latest iteration is input in the compute_step method too, passed from
    // the Solver class, but it was more important to unify the compute_step calling with just one syntax.
  public:
    ChordsStepper(std::function<double(double)> fun, bool aitken_mode, Eigen::Vector2d _int);
    Eigen::Vector2d compute_step(Eigen::Vector2d previous_iteration) override;
};
 
template <typename T>
class BisectionStepper : public StepperBase<T> {
  private:
    double left_edge, right_edge;  
 
  public:
    BisectionStepper(std::function<double(double)> fun, bool aitken_mode, Eigen::Vector2d _int);
    Eigen::Vector2d compute_step(Eigen::Vector2d previous_iteration) override;
};
 
#endif  // ROOT_STEPPER_DEF_HPP