G4ExactHelixStepper Class Reference

#include <G4ExactHelixStepper.hh>

Inheritance diagram for G4ExactHelixStepper:

Public Member Functions
	G4ExactHelixStepper (G4Mag_EqRhs *EqRhs)
	~G4ExactHelixStepper ()
void	Stepper (const G4double y[], const G4double dydx[], G4double h, G4double yout[], G4double yerr[])
void	DumbStepper (const G4double y[], G4ThreeVector Bfld, G4double h, G4double yout[])
G4double	DistChord () const
virtual G4int	IntegratorOrder () const
Public Member Functions inherited from G4MagHelicalStepper
	G4MagHelicalStepper (G4Mag_EqRhs *EqRhs)
virtual	~G4MagHelicalStepper ()
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 49 of file G4ExactHelixStepper.hh.

Constructor & Destructor Documentation

G4ExactHelixStepper::G4ExactHelixStepper

(

G4Mag_EqRhs *

EqRhs

)

Definition at line 45 of file G4ExactHelixStepper.cc.

  : G4MagHelicalStepper(EqRhs),
    fBfieldValue(DBL_MAX, DBL_MAX, DBL_MAX),
    fPtrMagEqOfMot(EqRhs)
{
  ;
}

G4ExactHelixStepper::~G4ExactHelixStepper

(

)

Definition at line 53 of file G4ExactHelixStepper.cc.

{} 

Member Function Documentation

G4double G4ExactHelixStepper::DistChord ( ) const

virtual

Implements G4MagIntegratorStepper.

Definition at line 99 of file G4ExactHelixStepper.cc.

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

{
  // Implementation : must check whether h/R >  pi  !!
  //   If( h/R <  pi)   DistChord=h/2*std::tan(Ang_curve/4)
  //   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 G4ExactHelixStepper::DumbStepper ( const G4double  y[], G4ThreeVector  Bfld, G4double  h, G4double  yout[]  )

virtual

Implements G4MagHelicalStepper.

Definition at line 81 of file G4ExactHelixStepper.cc.

References G4MagHelicalStepper::AdvanceHelix(), FatalException, and G4Exception().

{
  // Assuming a constant field: solution is a helix

  AdvanceHelix(yIn, Bfld, h, yOut);

  G4Exception("G4ExactHelixStepper::DumbStepper",
              "GeomField0002", FatalException,
              "Should not be called. Stepper must do all the work." ); 
}  

G4int G4ExactHelixStepper::IntegratorOrder ( ) const

virtual

Implements G4MagIntegratorStepper.

Definition at line 125 of file G4ExactHelixStepper.cc.

{
  return 1; 
}

void G4ExactHelixStepper::Stepper ( const G4double  y[], const G4double  dydx[], G4double  h, G4double  yout[], G4double  yerr[]  )

virtual

Reimplemented from G4MagHelicalStepper.

Definition at line 56 of file G4ExactHelixStepper.cc.

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

{  
   const G4int nvar = 6;

   G4int i;
   G4ThreeVector Bfld_value;

   MagFieldEvaluate(yInput, Bfld_value);        
   AdvanceHelix(yInput, Bfld_value, hstep, yOut);

  // We are assuming a constant field: helix is exact
  //
  for(i=0;i<nvar;i++)
  {
    yErr[i] = 0.0 ;
  }

  fBfieldValue=Bfld_value;
}

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

• G4ExactHelixStepper.hh
• G4ExactHelixStepper.cc