G4TMagErrorStepper< T_Stepper, T_Equation, N > Class Template Reference

G4TMagErrorStepper is a templated version of G4MagErrorStepper. More...

#include <G4TMagErrorStepper.hh>

Inheritance diagram for G4TMagErrorStepper< T_Stepper, T_Equation, N >:

Public Member Functions
	G4TMagErrorStepper (T_Equation *EqRhs, G4int numberOfVariables, G4int numStateVariables=12)
virtual	~G4TMagErrorStepper ()=default
	G4TMagErrorStepper (const G4TMagErrorStepper &)=delete
G4TMagErrorStepper &	operator= (const G4TMagErrorStepper &)=delete
void	RightHandSide (G4double y[], G4double dydx[])
void	Stepper (const G4double yInput[], const G4double dydx[], G4double hstep, G4double yOutput[], G4double yError[]) override final
G4double	DistChord () const override final
G4StepperType	StepperType () const override
Public Member Functions inherited from G4MagIntegratorStepper
	G4MagIntegratorStepper (G4EquationOfMotion *Equation, G4int numIntegrationVariables, G4int numStateVariables=12, G4bool isFSAL=false)
virtual	~G4MagIntegratorStepper ()=default
	G4MagIntegratorStepper (const G4MagIntegratorStepper &)=delete
G4MagIntegratorStepper &	operator= (const G4MagIntegratorStepper &)=delete
void	NormaliseTangentVector (G4double vec[6])
void	NormalisePolarizationVector (G4double vec[12])
void	RightHandSide (const G4double y[], G4double dydx[]) const
void	RightHandSide (const G4double y[], G4double dydx[], G4double field[]) const
G4int	GetNumberOfVariables () const
G4int	GetNumberOfStateVariables () const
virtual G4int	IntegratorOrder () const =0
G4int	IntegrationOrder ()
G4EquationOfMotion *	GetEquationOfMotion ()
const G4EquationOfMotion *	GetEquationOfMotion () const
void	SetEquationOfMotion (G4EquationOfMotion *newEquation)
unsigned long	GetfNoRHSCalls ()
void	ResetfNORHSCalls ()
G4bool	IsFSAL () const
G4bool	isQSS () const
void	SetIsQSS (G4bool val)

Additional Inherited Members
Protected Member Functions inherited from G4MagIntegratorStepper
void	SetIntegrationOrder (G4int order)
void	SetFSAL (G4bool flag=true)

Detailed Description

template<class T_Stepper, class T_Equation, unsigned int N>
class G4TMagErrorStepper< T_Stepper, T_Equation, N >

G4TMagErrorStepper is a templated version of G4MagErrorStepper.

Definition at line 49 of file G4TMagErrorStepper.hh.

Constructor & Destructor Documentation

G4TMagErrorStepper() [1/2]

template<class T_Stepper, class T_Equation, unsigned int N>

G4TMagErrorStepper< T_Stepper, T_Equation, N >::G4TMagErrorStepper ( T_Equation * EqRhs, G4int numberOfVariables, G4int numStateVariables = 12 )

inline

Definition at line 53 of file G4TMagErrorStepper.hh.

      : G4MagIntegratorStepper(EqRhs, numberOfVariables, numStateVariables)
      , fEquation_Rhs(EqRhs) { ; }

Referenced by G4TMagErrorStepper(), and operator=().

~G4TMagErrorStepper()

template<class T_Stepper, class T_Equation, unsigned int N>

virtual G4TMagErrorStepper< T_Stepper, T_Equation, N >::~G4TMagErrorStepper ( )

virtualdefault

G4TMagErrorStepper() [2/2]

template<class T_Stepper, class T_Equation, unsigned int N>

G4TMagErrorStepper< T_Stepper, T_Equation, N >::G4TMagErrorStepper ( const G4TMagErrorStepper< T_Stepper, T_Equation, N > & )

delete

Member Function Documentation

DistChord()

template<class T_Stepper, class T_Equation, unsigned int N>

G4double G4TMagErrorStepper< T_Stepper, T_Equation, N >::DistChord ( ) const

inlinefinaloverridevirtual

Estimates the maximum distance of a chord from the true path over the segment last integrated.

Implements G4MagIntegratorStepper.

Definition at line 154 of file G4TMagErrorStepper.hh.

{
  // Estimate the maximum distance from the curve to the chord
  //
  //  We estimate this using the distance of the midpoint to
  //  chord (the line between
  //
  //  Method below is good only for angle deviations < 2 pi,
  //   This restriction should not a problem for the Runge cutta methods,
  //   which generally cannot integrate accurately for large angle deviations.
  G4double distLine, distChord;
 
  if(fInitialPoint != fFinalPoint)
  {
    distLine = G4LineSection::Distline(fMidPoint, fInitialPoint, fFinalPoint);
    // This is a class method that gives distance of Mid
    //  from the Chord between the Initial and Final points.
    
    distChord = distLine;
  }
  else
  {
     distChord = (fMidPoint - fInitialPoint).mag();
  }
  
  return distChord;
}

operator=()

template<class T_Stepper, class T_Equation, unsigned int N>

G4TMagErrorStepper & G4TMagErrorStepper< T_Stepper, T_Equation, N >::operator= ( const G4TMagErrorStepper< T_Stepper, T_Equation, N > & )

delete

RightHandSide()

template<class T_Stepper, class T_Equation, unsigned int N>

void G4TMagErrorStepper< T_Stepper, T_Equation, N >::RightHandSide ( G4double y[], G4double dydx[] )

inline

Definition at line 63 of file G4TMagErrorStepper.hh.

    {
      fEquation_Rhs->T_Equation::RightHandSide(y, dydx);
    }

Referenced by Stepper().

Stepper()

template<class T_Stepper, class T_Equation, unsigned int N>

void G4TMagErrorStepper< T_Stepper, T_Equation, N >::Stepper ( const G4double y[], const G4double dydx[], G4double h, G4double yout[], G4double yerr[] )

inlinefinaloverridevirtual

The stepper for the Runge Kutta integration. The stepsize is fixed, with the step size given by 'h'. Integrates ODE starting values y[0 to 6]. Outputs yout[] and its estimated error yerr[].

Parameters

[in]	y	Starting values array of integration variables.
[in]	dydx	Derivatives array.
[in]	h	The given step size.
[out]	yout	Integration output.
[out]	yerr	The estimated error.

Implements G4MagIntegratorStepper.

Definition at line 95 of file G4TMagErrorStepper.hh.

{
  const unsigned int maxvar = GetNumberOfStateVariables();
  
  //  Saving yInput because yInput and yOutput can be aliases for same array
  for(unsigned int i = 0; i < N; ++i)
     yInitial[i] = yInput[i];
  yInitial[7] =
     yInput[7];  // Copy the time in case ... even if not really needed
  yMiddle[7]  = yInput[7];  // Copy the time from initial value
  yOneStep[7] = yInput[7];  // As it contributes to final value of yOutput ?
  // yOutput[7] = yInput[7];  // -> dumb stepper does it too for RK4
  for(unsigned int i = N; i < maxvar; ++i)
     yOutput[i] = yInput[i];
 
  G4double halfStep = hstep * 0.5;
  
  // Do two half steps
  
  static_cast<T_Stepper*>(this)->DumbStepper(yInitial, dydx, halfStep,
                                               yMiddle);
  this->RightHandSide(yMiddle, dydxMid);
  static_cast<T_Stepper*>(this)->DumbStepper(yMiddle, dydxMid, halfStep,
                                             yOutput);
  
  // Store midpoint, chord calculation
  
  fMidPoint = G4ThreeVector(yMiddle[0], yMiddle[1], yMiddle[2]);
  
  // Do a full Step
  static_cast<T_Stepper*>(this)->DumbStepper(yInitial, dydx, hstep, yOneStep);
  for(unsigned int i = 0; i < N; ++i)
  {
    yError[i] = yOutput[i] - yOneStep[i];
    yOutput[i] +=
       yError[i] *
       T_Stepper::IntegratorCorrection;  // Provides accuracy increased
    // by 1 order via the
    // Richardson Extrapolation
  }
 
  fInitialPoint = G4ThreeVector(yInitial[0], yInitial[1], yInitial[2]);
  fFinalPoint   = G4ThreeVector(yOutput[0], yOutput[1], yOutput[2]);
  
  return;
}

StepperType()

template<class T_Stepper, class T_Equation, unsigned int N>

G4StepperType G4TMagErrorStepper< T_Stepper, T_Equation, N >::StepperType ( ) const

inlineoverridevirtual

Returns the stepper type ID ('kUserStepper'). This function should be overriden in derived classes.

Reimplemented from G4MagIntegratorStepper.

Definition at line 72 of file G4TMagErrorStepper.hh.

{ return kTMagErrorStepper; }

Referenced by StepperType().

---

The documentation for this class was generated from the following file:

• G4TMagErrorStepper.hh