G4HelixExplicitEuler Class Reference

#include <G4HelixExplicitEuler.hh>

Inheritance diagram for G4HelixExplicitEuler:

Public Member Functions
	G4HelixExplicitEuler (G4Mag_EqRhs *EqRhs)
	~G4HelixExplicitEuler ()
void	Stepper (const G4double y[], const G4double *, G4double h, G4double yout[], G4double yerr[])
void	DumbStepper (const G4double y[], G4ThreeVector Bfld, G4double h, G4double yout[])
G4double	DistChord () const
G4int	IntegratorOrder () const
Public Member Functions inherited from G4MagHelicalStepper
	G4MagHelicalStepper (G4Mag_EqRhs *EqRhs)
virtual	~G4MagHelicalStepper ()
virtual void	Stepper (const G4double y[], const G4double dydx[], G4double h, G4double yout[], G4double yerr[])
G4double	DistChord () const
Public Member Functions inherited from G4MagIntegratorStepper
	G4MagIntegratorStepper (G4EquationOfMotion *Equation, G4int numIntegrationVariables, G4int numStateVariables=12)
virtual	~G4MagIntegratorStepper ()
virtual void	ComputeRightHandSide (const G4double y[], G4double dydx[])
void	NormaliseTangentVector (G4double vec[6])
void	NormalisePolarizationVector (G4double vec[12])
void	RightHandSide (const double y[], double dydx[])
G4int	GetNumberOfVariables () const
G4int	GetNumberOfStateVariables () const
G4EquationOfMotion *	GetEquationOfMotion ()
void	SetEquationOfMotion (G4EquationOfMotion *newEquation)

Additional Inherited Members
Protected Member Functions inherited from G4MagHelicalStepper
void	LinearStep (const G4double yIn[], G4double h, G4double yHelix[]) const
void	AdvanceHelix (const G4double yIn[], G4ThreeVector Bfld, G4double h, G4double yHelix[], G4double yHelix2[]=0)
void	MagFieldEvaluate (const G4double y[], G4ThreeVector &Bfield)
G4double	GetInverseCurve (const G4double Momentum, const G4double Bmag)
void	SetAngCurve (const G4double Ang)
G4double	GetAngCurve () const
void	SetCurve (const G4double Curve)
G4double	GetCurve () const
void	SetRadHelix (const G4double Rad)
G4double	GetRadHelix () const

Detailed Description

Definition at line 48 of file G4HelixExplicitEuler.hh.

Constructor & Destructor Documentation

G4HelixExplicitEuler::G4HelixExplicitEuler ( G4Mag_EqRhs *  EqRhs )

inline

Definition at line 52 of file G4HelixExplicitEuler.hh.

      : G4MagHelicalStepper(EqRhs) {}

G4HelixExplicitEuler::~G4HelixExplicitEuler ( )

inline

Definition at line 55 of file G4HelixExplicitEuler.hh.

{}

Member Function Documentation

G4double G4HelixExplicitEuler::DistChord ( ) const

virtual

Implements G4MagIntegratorStepper.

Definition at line 78 of file G4HelixExplicitEuler.cc.

References G4MagHelicalStepper::GetAngCurve(), G4MagHelicalStepper::GetRadHelix(), python.hepunit::pi, and python.hepunit::twopi.

{
  // Implementation : must check whether h/R > 2 pi  !!
  //   If( h/R <  pi) use G4LineSection::DistLine
  //   Else           DistChord=R_helix
  //
  G4double distChord;
  G4double Ang_curve=GetAngCurve();

      
     if(Ang_curve<=pi){
       distChord=GetRadHelix()*(1-std::cos(0.5*Ang_curve));
     }
         else 
         if(Ang_curve<twopi){
           distChord=GetRadHelix()*(1+std::cos(0.5*(twopi-Ang_curve)));
         }
         else{
          distChord=2.*GetRadHelix();  
         }

  return distChord;
  
}

void G4HelixExplicitEuler::DumbStepper ( const G4double  y[], G4ThreeVector  Bfld, G4double  h, G4double  yout[]  )

virtual

Implements G4MagHelicalStepper.

Definition at line 103 of file G4HelixExplicitEuler.cc.

References G4MagHelicalStepper::AdvanceHelix().

{
    
       AdvanceHelix(yIn, Bfld, h, yOut);
               
}  

G4int G4HelixExplicitEuler::IntegratorOrder ( ) const

inlinevirtual

Implements G4MagIntegratorStepper.

Definition at line 74 of file G4HelixExplicitEuler.hh.

{ return 1; }

void G4HelixExplicitEuler::Stepper	(	const G4double	y[],
		const G4double *	,
		G4double	h,
		G4double	yout[],
		G4double	yerr[]
	)

Definition at line 43 of file G4HelixExplicitEuler.cc.

References G4MagHelicalStepper::AdvanceHelix(), and G4MagHelicalStepper::MagFieldEvaluate().

{

 //Estimation of the Stepping Angle

  G4ThreeVector Bfld;
  MagFieldEvaluate(yInput, Bfld); 
  
  const G4int nvar = 6 ;
  G4int i;
  G4double      yTemp[7], yIn[7] ;
  G4ThreeVector  Bfld_midpoint;
  //  Saving yInput because yInput and yOut can be aliases for same array
        for(i=0;i<nvar;i++) yIn[i]=yInput[i];
     
        G4double h = Step * 0.5;
 
     // Do full step and two half steps
        G4double yTemp2[7];
        AdvanceHelix(yIn,   Bfld,  h, yTemp2,yTemp);
        MagFieldEvaluate(yTemp2, Bfld_midpoint) ;     
        AdvanceHelix(yTemp2, Bfld_midpoint, h, yOut);
    
     // Error estimation
        for(i=0;i<nvar;i++) {
         yErr[i] = yOut[i] - yTemp[i] ;
       }
    
}

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

• G4HelixExplicitEuler.hh
• G4HelixExplicitEuler.cc