G4ILawTruncatedExp Class Reference

#include <G4ILawTruncatedExp.hh>

Inheritance diagram for G4ILawTruncatedExp:

Public Member Functions
	G4ILawTruncatedExp (G4String name="expForceInteractionLaw")
virtual	~G4ILawTruncatedExp ()
virtual G4double	ComputeEffectiveCrossSectionAt (G4double length) const
virtual G4double	ComputeNonInteractionProbabilityAt (G4double length) const
virtual G4double	SampleInteractionLength ()
virtual G4double	UpdateInteractionLengthForStep (G4double truePathLength)
virtual G4bool	IsSingular () const
void	SetForceCrossSection (G4double xs)
void	SetMaximumDistance (G4double d)
G4double	GetMaximumDistance () const
G4double	GetInteractionDistance () const
Public Member Functions inherited from G4VBiasingInteractionLaw
	G4VBiasingInteractionLaw (G4String name)
virtual	~G4VBiasingInteractionLaw ()
const G4String &	GetName () const
virtual G4double	ComputeNonInteractionProbabilityAt (G4double length) const =0
virtual G4double	ComputeEffectiveCrossSectionAt (G4double length) const =0
virtual G4bool	IsSingular () const
virtual G4bool	IsEffectiveCrossSectionInfinite () const
G4double	Sample ()
G4double	UpdateForStep (G4double truePathLength)
G4double	GetSampledInteractionLength () const

Additional Inherited Members
virtual G4double	SampleInteractionLength ()=0
virtual G4double	UpdateInteractionLengthForStep (G4double)

Detailed Description

Definition at line 45 of file G4ILawTruncatedExp.hh.

Constructor & Destructor Documentation

G4ILawTruncatedExp()

G4ILawTruncatedExp::G4ILawTruncatedExp

(

G4String

name = "expForceInteractionLaw"

)

Definition at line 31 of file G4ILawTruncatedExp.cc.

  : G4VBiasingInteractionLaw(name),
    fMaximumDistance(0.0),
    fCrossSection(0.0),
    fCrossSectionDefined(false),
    fIsSingular(false)
{}

~G4ILawTruncatedExp()

G4ILawTruncatedExp::~G4ILawTruncatedExp ( )

virtual

Definition at line 39 of file G4ILawTruncatedExp.cc.

{}

Member Function Documentation

ComputeEffectiveCrossSectionAt()

G4double G4ILawTruncatedExp::ComputeEffectiveCrossSectionAt ( G4double  length ) const

virtual

Implements G4VBiasingInteractionLaw.

Definition at line 58 of file G4ILawTruncatedExp.cc.

{
  if ( !fCrossSectionDefined )
    {
      G4Exception("G4ILawTruncatedExp::ComputeEffectiveCrossSection(..)",
          "BIAS.GEN.10",
          JustWarning,
          "Cross-section value requested, but has not been defined yet. Assumes 0 !");
      // -- zero cross-section, returns the limit form of the effective cross-section:
      return 1.0 / ( fMaximumDistance - distance );
    }
  G4double denum = 1.0 - std::exp( -fCrossSection * ( fMaximumDistance - distance) );
  return fCrossSection / denum;
}

Referenced by G4ILawCommonTruncatedExp::ComputeEffectiveCrossSectionAt().

ComputeNonInteractionProbabilityAt()

G4double G4ILawTruncatedExp::ComputeNonInteractionProbabilityAt ( G4double  length ) const

virtual

Implements G4VBiasingInteractionLaw.

Definition at line 73 of file G4ILawTruncatedExp.cc.

{
  if (!fCrossSectionDefined)
    {
      G4Exception("G4ILawTruncatedExp::ComputeNonInteractionProbability(..)",
          "BIAS.GEN.11",
          JustWarning,
          "Non interaction probability value requested, but cross section has not been defined yet. Assumes it to be 0 !");
      // -- return limit case of null cross-section:
      return 1.0 - distance / fMaximumDistance;
    }
  G4double   num = 1.0 - std::exp( -fCrossSection*distance         );
  G4double denum = 1.0 - std::exp( -fCrossSection*fMaximumDistance );
  return 1.0 - num/denum;
}

Referenced by G4ILawCommonTruncatedExp::ComputeNonInteractionProbabilityAt().

GetInteractionDistance()

G4double G4ILawTruncatedExp::GetInteractionDistance ( ) const

inline

Definition at line 66 of file G4ILawTruncatedExp.hh.

{ return fInteractionDistance; }

Referenced by G4ILawCommonTruncatedExp::GetInteractionDistance().

GetMaximumDistance()

G4double G4ILawTruncatedExp::GetMaximumDistance ( ) const

inline

Definition at line 65 of file G4ILawTruncatedExp.hh.

{ return fMaximumDistance;}

Referenced by G4ILawCommonTruncatedExp::GetMaximumDistance().

IsSingular()

virtual G4bool G4ILawTruncatedExp::IsSingular ( ) const

inlinevirtual

Reimplemented from G4VBiasingInteractionLaw.

Definition at line 58 of file G4ILawTruncatedExp.hh.

{return fIsSingular;}

Referenced by G4ILawCommonTruncatedExp::IsSingular().

SampleInteractionLength()

G4double G4ILawTruncatedExp::SampleInteractionLength ( )

virtual

Implements G4VBiasingInteractionLaw.

Definition at line 89 of file G4ILawTruncatedExp.cc.

{
  if ( !fCrossSectionDefined )
    {
      G4Exception("G4ILawTruncatedExp::Sample(..)",
          "BIAS.GEN.12",
          JustWarning,
          "Trying to sample while cross-section is not defined, assuming 0 !");
      fInteractionDistance = G4UniformRand() * fMaximumDistance;
      return fInteractionDistance;
    }
  fInteractionDistance = -std::log(1.0 - G4UniformRand()* (1.0 - std::exp(-fCrossSection*fMaximumDistance)))/fCrossSection;
  return fInteractionDistance;
}

SetForceCrossSection()

void G4ILawTruncatedExp::SetForceCrossSection

(

G4double

xs

)

Definition at line 42 of file G4ILawTruncatedExp.cc.

{
  if (crossSection < 0.0)
    {
      G4Exception("G4ILawTruncatedExp::SetForceCrossSection(..)",
          "BIAS.GEN.09",
          JustWarning,
          "Cross-section value passed is negative. It is set to zero !");
      fIsSingular  = true;
      crossSection = 0.0;
    }
  fIsSingular          = false;
  fCrossSectionDefined = true;
  fCrossSection        = crossSection;
}

Referenced by G4ILawCommonTruncatedExp::SetForceCrossSection().

SetMaximumDistance()

void G4ILawTruncatedExp::SetMaximumDistance ( G4double  d )

inline

Definition at line 64 of file G4ILawTruncatedExp.hh.

{ fMaximumDistance = d;}

Referenced by G4ILawCommonTruncatedExp::SetMaximumDistance().

UpdateInteractionLengthForStep()

G4double G4ILawTruncatedExp::UpdateInteractionLengthForStep ( G4double  truePathLength )

virtual

Reimplemented from G4VBiasingInteractionLaw.

Definition at line 105 of file G4ILawTruncatedExp.cc.

{
  fInteractionDistance -= truePathLength;
  fMaximumDistance     -= truePathLength;
  
  if ( fInteractionDistance < 0 )
    {
      G4ExceptionDescription ed;
      ed << " Negative number of interaction length for `" << GetName() << "' " << fInteractionDistance << ", set it to zero !" << G4endl; 
      G4Exception("G4ILawTruncatedExp::UpdateInteractionLengthForStep(...)",
          "BIAS.GEN.13",
          JustWarning,
          "Trying to sample while cross-section is not defined, assuming 0 !");
      fInteractionDistance = 0.;
    }
  
  return  fInteractionDistance;
}

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

• G4ILawTruncatedExp.hh
• G4ILawTruncatedExp.cc