G4NystromRK4 Class Reference

#include <G4NystromRK4.hh>

Inheritance diagram for G4NystromRK4:

Public Member Functions
virtual G4double	DistChord () const override
	G4NystromRK4 (G4Mag_EqRhs *EquationMotion, G4double distanceConstField=0.0)
G4double	GetDistanceForConstantField () const
G4EquationOfMotion *	GetEquationOfMotion ()
const G4EquationOfMotion *	GetEquationOfMotion () const
unsigned long	GetfNoRHSCalls ()
G4int	GetNumberOfStateVariables () const
G4int	GetNumberOfVariables () const
G4int	IntegrationOrder ()
virtual G4int	IntegratorOrder () const override
G4bool	IsFSAL () const
void	NormalisePolarizationVector (G4double vec[12])
void	NormaliseTangentVector (G4double vec[6])
void	ResetfNORHSCalls ()
void	RightHandSide (const G4double y[], G4double dydx[]) const
void	RightHandSide (const G4double y[], G4double dydx[], G4double field[]) const
void	SetDistanceForConstantField (G4double length)
void	SetEquationOfMotion (G4EquationOfMotion *newEquation)
virtual void	Stepper (const G4double y[], const G4double dydx[], G4double hstep, G4double yOut[], G4double yError[]) override
	~G4NystromRK4 ()

Protected Member Functions
void	SetFSAL (G4bool flag=true)
void	SetIntegrationOrder (G4int order)

Private Member Functions
G4double	GetFCof ()
G4CachedMagneticField *	GetField ()
const G4CachedMagneticField *	GetField () const
void	GetFieldValue (const G4double point[4], G4double field[3])

Private Attributes
std::unique_ptr< G4CachedMagneticField >	fCachedField
G4double	fCoefficient = 0.0
G4ThreeVector	fEndPoint
G4EquationOfMotion *	fEquation_Rhs = nullptr
G4ThreeVector	fInitialPoint
G4int	fIntegrationOrder = -1
G4double	fInverseMomentum = 0.0
G4bool	fIsFSAL = false
G4ThreeVector	fMidPoint
G4double	fMomentum = 0.0
G4double	fMomentum2 = 0.0
const G4int	fNoIntegrationVariables = 0
unsigned long	fNoRHSCalls = 0UL
const G4int	fNoStateVariables = 0

Detailed Description

Definition at line 51 of file G4NystromRK4.hh.

Constructor & Destructor Documentation

G4NystromRK4()

G4NystromRK4::G4NystromRK4	(	G4Mag_EqRhs *	EquationMotion,
		G4double	distanceConstField = 0.0
	)

Definition at line 51 of file G4NystromRK4.cc.

  : G4MagIntegratorStepper(equation, INTEGRATED_COMPONENTS)
{
    if (distanceConstField > 0)
    {
        SetDistanceForConstantField(distanceConstField);
    }
}

References SetDistanceForConstantField().

~G4NystromRK4()

G4NystromRK4::~G4NystromRK4 ( )

inline

Definition at line 58 of file G4NystromRK4.hh.

{}

Member Function Documentation

DistChord()

G4double G4NystromRK4::DistChord ( ) const

overridevirtual

Implements G4MagIntegratorStepper.

Definition at line 183 of file G4NystromRK4.cc.

{
    return G4LineSection::Distline(fMidPoint, fInitialPoint, fEndPoint);
}

References G4LineSection::Distline(), fEndPoint, fInitialPoint, and fMidPoint.

GetDistanceForConstantField()

G4double G4NystromRK4::GetDistanceForConstantField

(

)

const

Definition at line 206 of file G4NystromRK4.cc.

{
  if (GetField() == nullptr)
  {
    return 0.0;
  }
  return GetField()->GetConstDistance(); 
}

References G4CachedMagneticField::GetConstDistance(), and GetField().

GetEquationOfMotion() [1/2]

G4EquationOfMotion * G4MagIntegratorStepper::GetEquationOfMotion ( )

inlineinherited

Referenced by G4MagInt_Driver::GetEquationOfMotion(), G4OldMagIntDriver::GetEquationOfMotion(), GetField(), G4DormandPrince745::GetSpecificEquation(), SetDistanceForConstantField(), G4RKG3_Stepper::StepNoErr(), and G4RKG3_Stepper::Stepper().

GetEquationOfMotion() [2/2]

const G4EquationOfMotion * G4MagIntegratorStepper::GetEquationOfMotion ( ) const

inlineinherited

GetFCof()

G4double G4NystromRK4::GetFCof ( )

inlineprivate

Referenced by Stepper().

GetField() [1/2]

G4CachedMagneticField * G4NystromRK4::GetField ( )

private

Definition at line 215 of file G4NystromRK4.cc.

{
  return dynamic_cast<G4CachedMagneticField*>(GetEquationOfMotion()->GetFieldObj());
}

References G4MagIntegratorStepper::GetEquationOfMotion(), and G4EquationOfMotion::GetFieldObj().

Referenced by GetDistanceForConstantField(), GetField(), and SetDistanceForConstantField().

GetField() [2/2]

const G4CachedMagneticField * G4NystromRK4::GetField ( ) const

private

Definition at line 220 of file G4NystromRK4.cc.

{
  return const_cast<G4NystromRK4*>(this)->GetField();
}

References GetField().

GetFieldValue()

void G4NystromRK4::GetFieldValue ( const G4double  point[4], G4double  field[3]  )

inlineprivate

Referenced by Stepper().

GetfNoRHSCalls()

unsigned long G4MagIntegratorStepper::GetfNoRHSCalls ( )

inlineinherited

GetNumberOfStateVariables()

G4int G4MagIntegratorStepper::GetNumberOfStateVariables ( ) const

inlineinherited

Referenced by G4BogackiShampine45::G4BogackiShampine45(), G4CashKarpRKF45::G4CashKarpRKF45(), G4SimpleRunge::G4SimpleRunge(), G4TSimpleRunge< T_Equation, N >::G4TSimpleRunge(), G4TsitourasRK45::G4TsitourasRK45(), G4BogackiShampine23::makeStep(), G4RK547FEq1::makeStep(), G4RK547FEq2::makeStep(), G4RK547FEq3::makeStep(), G4ConstRK4::Stepper(), G4MagErrorStepper::Stepper(), and G4TMagErrorStepper< T_Stepper, T_Equation, N >::Stepper().

GetNumberOfVariables()

G4int G4MagIntegratorStepper::GetNumberOfVariables ( ) const

inlineinherited

Referenced by G4ExplicitEuler::DumbStepper(), G4ImplicitEuler::DumbStepper(), G4ClassicalRK4::DumbStepper(), G4ChordFinder::G4ChordFinder(), G4BogackiShampine45::GetLastDydx(), G4DoLoMcPriRK34::Interpolate(), G4TsitourasRK45::Interpolate(), G4DormandPrince745::Interpolate4thOrder(), G4DormandPrince745::Interpolate5thOrder(), G4DormandPrinceRK56::Interpolate_high(), G4DormandPrinceRK56::Interpolate_low(), G4BogackiShampine45::InterpolateHigh(), G4BogackiShampine23::makeStep(), G4RK547FEq1::makeStep(), G4RK547FEq2::makeStep(), G4RK547FEq3::makeStep(), G4DormandPrinceRK56::SetupInterpolate_high(), G4DormandPrinceRK56::SetupInterpolate_low(), G4DormandPrince745::SetupInterpolation5thOrder(), G4BogackiShampine45::SetupInterpolationHigh(), G4BogackiShampine45::Stepper(), G4CashKarpRKF45::Stepper(), G4DoLoMcPriRK34::Stepper(), G4DormandPrinceRK56::Stepper(), G4DormandPrinceRK78::Stepper(), G4MagErrorStepper::Stepper(), G4TsitourasRK45::Stepper(), and G4DormandPrince745::Stepper().

IntegrationOrder()

G4int G4MagIntegratorStepper::IntegrationOrder ( )

inlineinherited

IntegratorOrder()

virtual G4int G4NystromRK4::IntegratorOrder ( ) const

inlineoverridevirtual

Implements G4MagIntegratorStepper.

Definition at line 71 of file G4NystromRK4.hh.

{ return 4; }

IsFSAL()

G4bool G4MagIntegratorStepper::IsFSAL ( ) const

inlineinherited

NormalisePolarizationVector()

void G4MagIntegratorStepper::NormalisePolarizationVector ( G4double  vec[12] )

inlineinherited

Referenced by G4SimpleHeum::DumbStepper(), and G4ClassicalRK4::DumbStepper().

NormaliseTangentVector()

void G4MagIntegratorStepper::NormaliseTangentVector ( G4double  vec[6] )

inlineinherited

ResetfNORHSCalls()

void G4MagIntegratorStepper::ResetfNORHSCalls ( )

inlineinherited

RightHandSide() [1/2]

void G4MagIntegratorStepper::RightHandSide ( const G4double  y[], G4double  dydx[]  ) const

inlineinherited

Referenced by G4MagInt_Driver::AccurateAdvance(), G4OldMagIntDriver::AccurateAdvance(), G4ImplicitEuler::DumbStepper(), G4SimpleHeum::DumbStepper(), G4SimpleRunge::DumbStepper(), G4ClassicalRK4::DumbStepper(), G4MagInt_Driver::GetDerivatives(), G4OldMagIntDriver::GetDerivatives(), G4BogackiShampine23::makeStep(), G4RK547FEq1::makeStep(), G4RK547FEq2::makeStep(), G4RK547FEq3::makeStep(), G4DormandPrinceRK56::SetupInterpolate_high(), G4DormandPrinceRK56::SetupInterpolate_low(), G4DormandPrince745::SetupInterpolation5thOrder(), G4BogackiShampine45::SetupInterpolationHigh(), G4BogackiShampine45::Stepper(), G4CashKarpRKF45::Stepper(), G4DoLoMcPriRK34::Stepper(), G4DormandPrinceRK56::Stepper(), G4DormandPrinceRK78::Stepper(), G4MagErrorStepper::Stepper(), G4TsitourasRK45::Stepper(), and G4DormandPrince745::Stepper().

RightHandSide() [2/2]

void G4MagIntegratorStepper::RightHandSide ( const G4double  y[], G4double  dydx[], G4double  field[]  ) const

inlineinherited

SetDistanceForConstantField()

void G4NystromRK4::SetDistanceForConstantField

(

G4double

length

)

Definition at line 188 of file G4NystromRK4.cc.

{
  if (GetField() == nullptr)
  {
    G4Exception("G4NystromRK4::SetDistanceForConstantField",
                "Nystrom 001", JustWarning,
        "Provided field is not G4CachedMagneticField. Changing field type.");
 
    fCachedField = std::unique_ptr<G4CachedMagneticField>(
       new G4CachedMagneticField(
           dynamic_cast<G4MagneticField*>(GetEquationOfMotion()->GetFieldObj()),
           length));
 
    GetEquationOfMotion()->SetFieldObj(fCachedField.get());
  }
  GetField()->SetConstDistance(length);
}

References fCachedField, G4Exception(), G4MagIntegratorStepper::GetEquationOfMotion(), GetField(), JustWarning, G4CachedMagneticField::SetConstDistance(), and G4EquationOfMotion::SetFieldObj().

Referenced by G4NystromRK4().

SetEquationOfMotion()

void G4MagIntegratorStepper::SetEquationOfMotion ( G4EquationOfMotion *  newEquation )

inlineinherited

Referenced by G4MagInt_Driver::SetEquationOfMotion(), and G4OldMagIntDriver::SetEquationOfMotion().

SetFSAL()

void G4MagIntegratorStepper::SetFSAL ( G4bool  flag = true )

inlineprotectedinherited

Referenced by G4BogackiShampine23::G4BogackiShampine23().

SetIntegrationOrder()

void G4MagIntegratorStepper::SetIntegrationOrder ( G4int  order )

inlineprotectedinherited

Referenced by G4BogackiShampine23::G4BogackiShampine23().

Stepper()

void G4NystromRK4::Stepper ( const G4double  y[], const G4double  dydx[], G4double  hstep, G4double  yOut[], G4double  yError[]  )

overridevirtual

Implements G4MagIntegratorStepper.

Definition at line 60 of file G4NystromRK4.cc.

{
    fInitialPoint = { y[0], y[1], y[2] };
 
    G4double field[3];
 
    constexpr G4double one_sixth= 1./6.;
    const G4double S5 = 0.5 * hstep;
    const G4double S4 = .25 * hstep;
    const G4double S6 = hstep * one_sixth;
   
    const G4double momentum2 = getValue2(y, Value3D::Momentum);
    if (notEquals(momentum2, fMomentum2))
    {
        fMomentum = std::sqrt(momentum2);
        fMomentum2 = momentum2;
        fInverseMomentum  = 1. / fMomentum;
        fCoefficient = GetFCof() * fInverseMomentum;
    }
    
    // Point 1
    const G4double K1[3] = { 
        fInverseMomentum * dydx[3], 
        fInverseMomentum * dydx[4], 
        fInverseMomentum * dydx[5]
    };
    
    // Point2
    G4double p[4] = {
        y[0] + S5 * (dydx[0] + S4 * K1[0]),
        y[1] + S5 * (dydx[1] + S4 * K1[1]),
        y[2] + S5 * (dydx[2] + S4 * K1[2]),
        y[7]
    };
 
    GetFieldValue(p, field);
  
    const G4double A2[3] = {
        dydx[0] + S5 * K1[0],
        dydx[1] + S5 * K1[1],
        dydx[2] + S5 * K1[2]
    };
 
    const G4double K2[3] = {
        (A2[1] * field[2] - A2[2] * field[1]) * fCoefficient,
        (A2[2] * field[0] - A2[0] * field[2]) * fCoefficient,
        (A2[0] * field[1] - A2[1] * field[0]) * fCoefficient
    };
 
    fMidPoint = { p[0], p[1], p[2] };
 
    // Point 3 with the same magnetic field
    const G4double A3[3] = {
        dydx[0] + S5 * K2[0],
        dydx[1] + S5 * K2[1],
        dydx[2] + S5 * K2[2]
    };
 
    const G4double K3[3] = {
        (A3[1] * field[2] - A3[2] * field[1]) * fCoefficient,
        (A3[2] * field[0] - A3[0] * field[2]) * fCoefficient,
        (A3[0] * field[1] - A3[1] * field[0]) * fCoefficient
    };
 
    // Point 4
    p[0] = y[0] + hstep * (dydx[0] + S5 * K3[0]);
    p[1] = y[1] + hstep * (dydx[1] + S5 * K3[1]);
    p[2] = y[2] + hstep * (dydx[2] + S5 * K3[2]);             
 
    GetFieldValue(p, field);
  
    const G4double A4[3] = {
        dydx[0] + hstep * K3[0],
        dydx[1] + hstep * K3[1],
        dydx[2] + hstep * K3[2]
    };
 
    const G4double K4[3] = {
        (A4[1] * field[2] - A4[2] * field[1]) * fCoefficient,
        (A4[2] * field[0] - A4[0] * field[2]) * fCoefficient,
        (A4[0] * field[1] - A4[1] * field[0]) * fCoefficient
    };
  
    // New position
    yOut[0] = y[0] + hstep * (dydx[0] + S6 * (K1[0] + K2[0] + K3[0]));
    yOut[1] = y[1] + hstep * (dydx[1] + S6 * (K1[1] + K2[1] + K3[1]));
    yOut[2] = y[2] + hstep * (dydx[2] + S6 * (K1[2] + K2[2] + K3[2]));
    // New direction
    yOut[3] = dydx[0] + S6 * (K1[0] + K4[0] + 2. * (K2[0] + K3[0]));
    yOut[4] = dydx[1] + S6 * (K1[1] + K4[1] + 2. * (K2[1] + K3[1]));
    yOut[5] = dydx[2] + S6 * (K1[2] + K4[2] + 2. * (K2[2] + K3[2]));
    // Pass Energy, time unchanged -- time is not integrated !!
    yOut[6] = y[6]; 
    yOut[7] = y[7];
 
    fEndPoint = { yOut[0], yOut[1], yOut[2] };
 
    // Errors
    yError[3] = hstep * std::fabs(K1[0] - K2[0] - K3[0] + K4[0]);
    yError[4] = hstep * std::fabs(K1[1] - K2[1] - K3[1] + K4[1]);
    yError[5] = hstep * std::fabs(K1[2] - K2[2] - K3[2] + K4[2]);
    yError[0] = hstep * yError[3];
    yError[1] = hstep * yError[4];
    yError[2] = hstep * yError[5];
    yError[3] *= fMomentum;
    yError[4] *= fMomentum;
    yError[5] *= fMomentum;
 
    // Normalize momentum
    const G4double normF = fMomentum / getValue(yOut, Value3D::Momentum);
    yOut[3] *= normF; 
    yOut[4] *= normF; 
    yOut[5] *= normF; 
 
    // My trial code:
    // G4double endMom2 = yOut[3]*yOut[3]+yOut[4]*yOut[4]+yOut[5]*yOut[5];
    // G4double normF = std::sqrt( startMom2 / endMom2 );  
}

References fCoefficient, fEndPoint, fInitialPoint, fInverseMomentum, fMidPoint, fMomentum, fMomentum2, GetFCof(), GetFieldValue(), field_utils::getValue(), field_utils::getValue2(), and anonymous_namespace{G4NystromRK4.cc}::notEquals().

Field Documentation

fCachedField

std::unique_ptr<G4CachedMagneticField> G4NystromRK4::fCachedField

private

Definition at line 90 of file G4NystromRK4.hh.

Referenced by SetDistanceForConstantField().

fCoefficient

G4double G4NystromRK4::fCoefficient = 0.0

private

Definition at line 85 of file G4NystromRK4.hh.

Referenced by Stepper().

fEndPoint

G4ThreeVector G4NystromRK4::fEndPoint

private

Definition at line 88 of file G4NystromRK4.hh.

Referenced by DistChord(), and Stepper().

fEquation_Rhs

G4EquationOfMotion* G4MagIntegratorStepper::fEquation_Rhs = nullptr

privateinherited

Definition at line 124 of file G4MagIntegratorStepper.hh.

fInitialPoint

G4ThreeVector G4NystromRK4::fInitialPoint

private

Definition at line 86 of file G4NystromRK4.hh.

Referenced by DistChord(), and Stepper().

fIntegrationOrder

G4int G4MagIntegratorStepper::fIntegrationOrder = -1

privateinherited

Definition at line 134 of file G4MagIntegratorStepper.hh.

fInverseMomentum

G4double G4NystromRK4::fInverseMomentum = 0.0

private

Definition at line 84 of file G4NystromRK4.hh.

Referenced by Stepper().

fIsFSAL

G4bool G4MagIntegratorStepper::fIsFSAL = false

privateinherited

Definition at line 136 of file G4MagIntegratorStepper.hh.

fMidPoint

G4ThreeVector G4NystromRK4::fMidPoint

private

Definition at line 87 of file G4NystromRK4.hh.

Referenced by DistChord(), and Stepper().

fMomentum

G4double G4NystromRK4::fMomentum = 0.0

private

Definition at line 82 of file G4NystromRK4.hh.

Referenced by Stepper().

fMomentum2

G4double G4NystromRK4::fMomentum2 = 0.0

private

Definition at line 83 of file G4NystromRK4.hh.

Referenced by Stepper().

fNoIntegrationVariables

const G4int G4MagIntegratorStepper::fNoIntegrationVariables = 0

privateinherited

Definition at line 125 of file G4MagIntegratorStepper.hh.

fNoRHSCalls

unsigned long G4MagIntegratorStepper::fNoRHSCalls = 0UL

mutableprivateinherited

Definition at line 128 of file G4MagIntegratorStepper.hh.

fNoStateVariables

const G4int G4MagIntegratorStepper::fNoStateVariables = 0

privateinherited

Definition at line 126 of file G4MagIntegratorStepper.hh.

---

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

• source/geometry/magneticfield/include/G4NystromRK4.hh
• source/geometry/magneticfield/src/G4NystromRK4.cc