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//
// $Id: G4ChordFinder.icc,v 1.14 2008/10/29 14:34:35 gcosmo Exp $
// GEANT4 tag $Name: geant4-09-04-beta-01 $
//
// G4ChordFinder inline implementations
//
// --------------------------------------------------------------------

inline 
void G4ChordFinder::SetIntegrationDriver(G4MagInt_Driver* IntegrationDriver)
{
  fIntgrDriver=IntegrationDriver;
}

inline
G4MagInt_Driver* G4ChordFinder::GetIntegrationDriver()
{
  return fIntgrDriver;
}

inline
G4bool G4ChordFinder::AcceptableMissDist(G4double dChordStep) const
{ 
  return (dChordStep <= fDeltaChord) ;
}

inline
void G4ChordFinder::SetChargeMomentumMass(G4double pCharge, // in e+ units
                                          G4double pMomentum,
                                          G4double pMass)
{
  fIntgrDriver-> SetChargeMomentumMass(pCharge, pMomentum, pMass);
}

inline
G4double G4ChordFinder::GetDeltaChord() const
{
  return fDeltaChord;
}

inline
void G4ChordFinder::SetDeltaChord(G4double newval)
{
  fDeltaChord=newval;
}

// ......................................................................
inline 
G4double G4ChordFinder::GetLastStepEstimateUnc()
{
  return fLastStepEstimate_Unconstrained;   
} 
inline 
void G4ChordFinder::SetLastStepEstimateUnc( G4double stepEst )
{
  fLastStepEstimate_Unconstrained = stepEst;    
}
inline
void G4ChordFinder::ResetStepEstimate()
{
  fLastStepEstimate_Unconstrained = DBL_MAX;    
}

// ......................................................................
inline G4int G4ChordFinder::GetNoCalls()     { return fNoCalls_FNC; }
inline G4int G4ChordFinder::GetNoTrials()    { return fTotalNoTrials_FNC; }
inline G4int G4ChordFinder::GetNoMaxTrials() { return fmaxTrials_FNC; } 

inline G4double G4ChordFinder::GetFirstFraction() { return fFirstFraction; } 
inline G4double G4ChordFinder::GetFractionLast()  { return fFractionLast; } 
inline G4double G4ChordFinder::GetFractionNextEstimate() 
{ return fFractionNextEstimate; } 
inline G4double G4ChordFinder::GetMultipleRadius()
{ return fMultipleRadius; } 

inline void G4ChordFinder::SetFirstFraction(G4double val){ fFirstFraction=val; }

inline G4int G4ChordFinder::SetVerbose( G4int newvalue )
{ 
  G4int oldval= fStatsVerbose; 
  fStatsVerbose = newvalue;
  return oldval; 
}

inline  
void    G4ChordFinder::AccumulateStatistics( G4int noTrials ) 
{
  // Statistics 
  fTotalNoTrials_FNC += noTrials; 
  fNoCalls_FNC++; 
  // if( noTrials >= fmaxTrials_FNC ){
    if (noTrials > fmaxTrials_FNC ) { 
      fmaxTrials_FNC=noTrials; 
      // fnoTimesMaxTrFNC=0; 
    } else { 
      // fnoTimesMaxTrFNC++; 
    } 
  // } 
}
// A  member that calculates the inverse parabolic through
// the three points (x,y) and returns the value x that, for the
// inverse parabolic, corresponds to y=0.
//
inline G4double G4ChordFinder::InvParabolic ( const G4double xa, const G4double ya,
				    const G4double xb, const G4double yb,
				    const G4double xc, const G4double yc )
{   	const G4double R = yb/yc,
	               S = yb/ya,
		       T = ya/yc;
        const G4double Q = (T-1)*(R-1)*(S-1);
	if (std::fabs(Q) <DBL_MIN ) return  DBL_MAX;
	
	const G4double P = S*(T*(R-T)*(xc-xb) - (1-R)*(xb-xa));
	return xb + P/Q;
}