#include <G4WeightWindowAlgorithm.hh>

Inheritance diagram for G4WeightWindowAlgorithm:

Public Member Functions
	G4WeightWindowAlgorithm (G4double upperLimitFactor=5, G4double survivalFactor=3, G4int maxNumberOfSplits=5)

	~G4WeightWindowAlgorithm () override

G4Nsplit_Weight	Calculate (G4double init_w, G4double lowerWeightBound) const override

Public Member Functions inherited from G4VWeightWindowAlgorithm
	G4VWeightWindowAlgorithm ()

virtual	~G4VWeightWindowAlgorithm ()

Detailed Description

Definition at line 53 of file G4WeightWindowAlgorithm.hh.

Constructor & Destructor Documentation

◆ G4WeightWindowAlgorithm()

G4WeightWindowAlgorithm::G4WeightWindowAlgorithm	(	G4double	upperLimitFactor = 5,
		G4double	survivalFactor = 3,
		G4int	maxNumberOfSplits = 5 )

Definition at line 33 of file G4WeightWindowAlgorithm.cc.

  : fUpperLimitFactor(upperLimitFactor),
    fSurvivalFactor(survivalFactor),
    fMaxNumberOfSplits(maxNumberOfSplits)
{
}

◆ ~G4WeightWindowAlgorithm()

G4WeightWindowAlgorithm::~G4WeightWindowAlgorithm ( )

overridedefault

Member Function Documentation

◆ Calculate()

G4Nsplit_Weight G4WeightWindowAlgorithm::Calculate	(	G4double	init_w,
		G4double	lowerWeightBound ) const

overridevirtual

Implements G4VWeightWindowAlgorithm.

Definition at line 46 of file G4WeightWindowAlgorithm.cc.

{
  G4double survivalWeight = lowerWeightBound * fSurvivalFactor;
  G4double upperWeight = lowerWeightBound * fUpperLimitFactor;
 
  // initialize return value for case weight in window
  //
  G4Nsplit_Weight nw;
  nw.fN = 1;
  nw.fW = init_w;
 
  if (init_w > upperWeight)
  {
    // splitting
    //
    G4double temp_wi_ws = init_w/upperWeight;
    auto  split_i = static_cast<G4int>(temp_wi_ws);
    if(split_i != temp_wi_ws)  { ++split_i; }
    G4double wi_ws = init_w/split_i;
 
    // values in case integer mode or in csae of double
    // mode and the lower number of splits will be diced
    //
    nw.fN = split_i;
    nw.fW = wi_ws;        
 
//TB     if (wi_ws <= fMaxNumberOfSplits) {
//TB       if (wi_ws > int_wi_ws) {
//TB         // double mode
//TB         G4double p2 =  wi_ws - int_wi_ws;
//TB         G4double r = G4UniformRand();
//TB         if (r<p2) {
//TB           nw.fN = int_wi_ws + 1;
//TB         }
//TB       }
//TB     }
//TB     else {
//TB       // fMaxNumberOfSplits < wi_ws
//TB       nw.fN = fMaxNumberOfSplits;
//TB       nw.fW = init_w/fMaxNumberOfSplits;
//TB     }
 
  }
  else if (init_w < lowerWeightBound)  // Russian roulette
  {
    G4double wi_ws = init_w/survivalWeight;
    G4double p = std::max(wi_ws,1./fMaxNumberOfSplits);
    G4double r = G4UniformRand();
    if (r<p)
    {
      nw.fW = init_w/p;
      nw.fN = 1;
    }
    else
    {
      nw.fW = 0;
      nw.fN = 0;
    }
  } 
  // else do nothing
 
  return nw;
}