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Diffstat (limited to 'kscreensaver/kdesavers/rkodesolver.h')
| -rw-r--r-- | kscreensaver/kdesavers/rkodesolver.h | 187 |
1 files changed, 0 insertions, 187 deletions
diff --git a/kscreensaver/kdesavers/rkodesolver.h b/kscreensaver/kdesavers/rkodesolver.h deleted file mode 100644 index d1f9d556..00000000 --- a/kscreensaver/kdesavers/rkodesolver.h +++ /dev/null @@ -1,187 +0,0 @@ -//============================================================================ -// -// Ordinary differential equation solver using the Runge-Kutta method. -// $Id$ -// Copyright (C) 2004 Georg Drenkhahn -// -// This file is free software; you can redistribute it and/or modify it under -// the terms of the GNU General Public License version 2 as published by the -// Free Software Foundation. -// -//============================================================================ - -#ifndef RKODESOLVER_H -#define RKODESOLVER_H - -// STL headers -#include <valarray> - -/** @brief Solver class to integrate a first-order ordinary differential - * equation (ODE) by means of a 6. order Runge-Kutta method. - * - * The ODE system must be given as the derivative - * dy/dx = f(x,y) - * with x in R and y in R^n. - * - * Within this class the function f() is a pure virtual function, which must be - * reimplemented in a derived class. - * - * No other special data type for vectors or matrices are needed besides the STL - * class std::valarray. */ -template<typename T> -class RkOdeSolver -{ - public: - /** @brief Constructor - * @param x Initial integration parameter - * @param y Initial function values of function to integrate - * @param dx Initial guess for step size. Will be automatically adjusted to - * guarantee required precision. - * @param eps Relative precision - * - * Initialises the solver with start conditions. */ - RkOdeSolver(const T& x=0.0, - const std::valarray<T>& y=std::valarray<T>(0), - const T& dx=0, - const T& eps=1e-6); - /** @brief Destructor */ - virtual ~RkOdeSolver(void); - - /** @brief Integrates the ordinary differential equation from the current x - * value to x+@a dx. - * @param dx x-interval size to integrate over starting from x. dx may be - * negative. - * - * The integration is performed by calling rkStepCheck() repeatedly until the - * desired x value is reached. */ - void integrate(const T& dx); - - // Accessors - - // get/set x value - /** @brief Get current x value. - * @return Reference of x value. */ - const T& X(void) const; - /** @brief Set current x value. - * @param a The value to be set. */ - void X(const T& a); - - // get/set y value - /** @brief Get current y value. - * @return Reference of y vector. */ - const std::valarray<T>& Y(void) const; - /** @brief Set current y values. - * @param a The vector to be set. */ - void Y(const std::valarray<T>& a); - - /** @brief Get current dy/dx value. - * @return Reference of dy/dx vector. */ - const std::valarray<T>& dYdX(void) const; - - // get/set dx value - /** @brief Get current estimated step size dX. - * @return Reference of dX value. */ - const T& dX(void) const; - /** @brief Set estimated step size dX. - * @param a The value to be set. */ - void dX(const T& a); - - // get/set eps value - /** @brief Get current presision. - * @return Reference of precision value. */ - const T& Eps(void) const; - /** @brief Set estimated presision. - * @param a The value to be set. */ - void Eps(const T& a); - - protected: - // purely virtual function which is integrated - /** @brief ODE function - * @param x Integration value - * @param y Function value - * @return Derivation - * - * This purely virtual function returns the value of dy/dx for the given - * parameter values of x and y. */ - virtual std::valarray<T> - f(const T& x, const std::valarray<T>& y) const = 0; - - private: - /** @brief Perform one integration step with a tolerable relative error given - * by ::mErr. - * @param dx Maximal step size, may be positive or negative depending on - * integration direction. - * @return Flag indicating if made absolute integration step was equal |@a dx - * | (true) less than |@a dx | (false). - * - * A new estimate for the maximum next step size is saved to ::mStep. The - * new values for x, y and f are saved in ::mX, ::mY and ::mDydx. */ - bool rkStepCheck(const T& dx); - /** @brief Perform one Runge-Kutta integration step forward with step size - * ::mStep - * @param dx Step size relative to current x value. - * @param yerr Reference to vector in which the estimated error made in y is - * returned. - * @return The y value after the step at x+@a dx. - * - * Stored current x,y values are not adjusted. */ - std::valarray<T> rkStep(const T& dx, std::valarray<T>& yerr) const; - - /** current x value */ - T mX; - /** current y value */ - std::valarray<T> mY; - /** current value of dy/dx */ - std::valarray<T> mDydx; - - /** allowed relative error */ - T mEps; - /** estimated step size for next Runge-Kutta step */ - T mStep; -}; - -// inline accessors - -template<typename T> -inline const T& -RkOdeSolver<T>::X(void) const -{ - return mX; -} - -template<typename T> -inline void -RkOdeSolver<T>::X(const T &a) -{ - mX = a; -} - -template<typename T> -inline const std::valarray<T>& -RkOdeSolver<T>::Y(void) const -{ - return mY; -} - -template<typename T> -inline const std::valarray<T>& -RkOdeSolver<T>::dYdX(void) const -{ - return mDydx; -} - -template<typename T> -inline const T& -RkOdeSolver<T>::dX(void) const -{ - return mStep; -} - -template<typename T> -inline const T& -RkOdeSolver<T>::Eps(void) const -{ - return mEps; -} - -#endif |