G4GoudsmitSaundersonTable Class Reference

#include <G4GoudsmitSaundersonTable.hh>

Public Member Functions
	G4GoudsmitSaundersonTable ()
	~G4GoudsmitSaundersonTable ()
G4double	SampleTheta (G4double, G4double, G4double)

Detailed Description

Definition at line 48 of file G4GoudsmitSaundersonTable.hh.

Constructor & Destructor Documentation

G4GoudsmitSaundersonTable::G4GoudsmitSaundersonTable

(

)

Definition at line 182 of file G4GoudsmitSaundersonTable.cc.

References G4cout, and G4endl.

{
  if(PDF == 0){ 
    G4cout << "### G4GoudsmitSaundersonTable loading PDF data" << G4endl;

    PDF = new G4double [76*11*320];
    CPDF= new G4double [76*11*320];

    LoadPDFandCPDFdata();
  }
}

G4GoudsmitSaundersonTable::~G4GoudsmitSaundersonTable

(

)

Definition at line 195 of file G4GoudsmitSaundersonTable.cc.

{
  if(PDF) {
    delete [] PDF;
    delete [] CPDF;
    PDF = 0;
  }
}

Member Function Documentation

G4double G4GoudsmitSaundersonTable::SampleTheta	(	G4double	lambda,
		G4double	Chia2,
		G4double	rndm
	)

Definition at line 205 of file G4GoudsmitSaundersonTable.cc.

References test::a, test::b, G4Log(), and rndm().

{ 
  //Benedito's procedure
  G4double A[11],ThisPDF[320],ThisCPDF[320];
  G4double coeff,Ckj,CkjPlus1,CkPlus1j,CkPlus1jPlus1,a,b,mmm,F;
  G4int Ind0,KIndex=0,JIndex=0,IIndex=0;


  ///////////////////////////////////////////////////////////////////////////
  // Find Lambda and Chia2 Index
  for(G4int k=0;k<75;k++){if((lambda>=LAMBDAN[k])&&(lambda<LAMBDAN[k+1])){KIndex=k;break;}}  
  for(G4int j=0;j<11;j++){A[j]=scrA[11*KIndex+j];}  
  for(G4int j=0;j<10;j++){if((Chia2>=A[j])&&(Chia2<A[j+1])){JIndex=j;break;}}

  ///////////////////////////////////////////////////////////////////////////
  // Calculate some necessary coefficients for PDF and CPDF interpolation 
  coeff=(G4Log(LAMBDAN[KIndex+1]/LAMBDAN[KIndex]))*(G4Log(A[JIndex+1]/A[JIndex]));
  Ckj=(G4Log(LAMBDAN[KIndex+1]/lambda))*(G4Log(A[JIndex+1]/Chia2))/coeff;
  CkjPlus1=(G4Log(LAMBDAN[KIndex+1]/lambda))*(G4Log(Chia2/A[JIndex]))/coeff;
  CkPlus1j=(G4Log(lambda/LAMBDAN[KIndex]))*(G4Log(A[JIndex+1]/Chia2))/coeff;
  CkPlus1jPlus1=(G4Log(lambda/LAMBDAN[KIndex]))*(G4Log(Chia2/A[JIndex]))/coeff;
  ///////////////////////////////////////////////////////////////////////////
  // Calculate Interpolated PDF and CPDF arrays
  Ind0=320*(11*KIndex+JIndex);
  for(G4int i=0 ; i<320 ;i++){
    ThisPDF[i]=Ckj*PDF[Ind0]+CkjPlus1*PDF[Ind0+320]+CkPlus1j*PDF[Ind0+3520]+CkPlus1jPlus1*PDF[Ind0+3840];
    ThisCPDF[i]=Ckj*CPDF[Ind0]+CkjPlus1*CPDF[Ind0+320]+CkPlus1j*CPDF[Ind0+3520]+CkPlus1jPlus1*CPDF[Ind0+3840];  
  // Find u Index using secant method
    if((i!=0)&&((rndm>=ThisCPDF[i-1])&&(rndm<ThisCPDF[i])))  {IIndex=i-1;break;}
    Ind0++;
  }

  ///////////////////////////////////////////////////////////////////////////
  //CPDF^-1(rndm)=x ==> CPDF(x)=rndm;
  a=uvalues[IIndex];
  b=uvalues[IIndex+1];
  
  do{
    mmm=0.5*(a+b);
    F=(ThisCPDF[IIndex]+(mmm-uvalues[IIndex])*ThisPDF[IIndex]
       +((mmm-uvalues[IIndex])*(mmm-uvalues[IIndex])
     *(ThisPDF[IIndex+1]-ThisPDF[IIndex]))
       /(2.*(uvalues[IIndex+1]-uvalues[IIndex])))-rndm;
    if(F>0.)b=mmm;
    else a=mmm;
  } while(std::fabs(b-a)>1.0e-9);

  return mmm;
}

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

• G4GoudsmitSaundersonTable.hh
• G4GoudsmitSaundersonTable.cc