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/*=========================================================================
Program: Visualization Toolkit
Module: vtkRungeKutta2.h
Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
All rights reserved.
See Copyright.txt or http://www.kitware.com/Copyright.htm for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notice for more information.
=========================================================================*/
/**
* @class vtkRungeKutta2
* @brief Integrate an initial value problem using 2nd
* order Runge-Kutta method.
*
*
* This is a concrete sub-class of vtkInitialValueProblemSolver.
* It uses a 2nd order Runge-Kutta method to obtain the values of
* a set of functions at the next time step.
*
* @sa
* vtkInitialValueProblemSolver vtkRungeKutta4 vtkRungeKutta45 vtkFunctionSet
*/
#ifndef vtkRungeKutta2_h
#define vtkRungeKutta2_h
#include "vtkCommonMathModule.h" // For export macro
#include "vtkInitialValueProblemSolver.h"
class VTKCOMMONMATH_EXPORT vtkRungeKutta2 : public vtkInitialValueProblemSolver
{
public:
vtkTypeMacro(vtkRungeKutta2, vtkInitialValueProblemSolver);
/**
* Construct a vtkRungeKutta2 with no initial FunctionSet.
*/
static vtkRungeKutta2* New();
using Superclass::ComputeNextStep;
//@{
/**
* Given initial values, xprev , initial time, t and a requested time
* interval, delT calculate values of x at t+delT (xnext).
* delTActual is always equal to delT.
* Since this class can not provide an estimate for the error error
* is set to 0.
* maxStep, minStep and maxError are unused.
* This method returns an error code representing the nature of
* the failure:
* OutOfDomain = 1,
* NotInitialized = 2,
* UnexpectedValue = 3
*/
int ComputeNextStep(double* xprev, double* xnext, double t, double& delT, double maxError,
double& error, void* userData) override
{
double minStep = delT;
double maxStep = delT;
double delTActual;
return this->ComputeNextStep(
xprev, nullptr, xnext, t, delT, delTActual, minStep, maxStep, maxError, error, userData);
}
int ComputeNextStep(double* xprev, double* dxprev, double* xnext, double t, double& delT,
double maxError, double& error, void* userData) override
{
double minStep = delT;
double maxStep = delT;
double delTActual;
return this->ComputeNextStep(
xprev, dxprev, xnext, t, delT, delTActual, minStep, maxStep, maxError, error, userData);
}
int ComputeNextStep(double* xprev, double* xnext, double t, double& delT, double& delTActual,
double minStep, double maxStep, double maxError, double& error, void* userData) override
{
return this->ComputeNextStep(
xprev, nullptr, xnext, t, delT, delTActual, minStep, maxStep, maxError, error, userData);
}
int ComputeNextStep(double* xprev, double* dxprev, double* xnext, double t, double& delT,
double& delTActual, double minStep, double maxStep, double maxError, double& error,
void* userData) override;
//@}
protected:
vtkRungeKutta2();
~vtkRungeKutta2() override;
private:
vtkRungeKutta2(const vtkRungeKutta2&) = delete;
void operator=(const vtkRungeKutta2&) = delete;
};
#endif
// VTK-HeaderTest-Exclude: vtkRungeKutta2.h