#include <G4DNASmoluchowskiDiffusion.hh>

Classes
struct	BoundingBox

Public Member Functions
	G4DNASmoluchowskiDiffusion (double epsilon=1e-5)

virtual	~G4DNASmoluchowskiDiffusion ()

double	GetRandomDistance (double _time, double D)

double	GetRandomTime (double distance, double D)

double	EstimateCrossingTime (double proba, double distance, double D)

void	PrepareReverseTable (double xmin, double xmax)

double	GetInverseProbability (double proba)

double	PlotInverse (double x, double )

double	Plot (double x, double )

void	InitialiseInverseProbability (double xmax=3e28)

Static Public Member Functions
static double	ComputeS (double r, double D, double t)

static double	ComputeDistance (double sTransform, double D, double t)

static double	ComputeTime (double sTransform, double D, double r)

static double	GetDifferential (double sTransform)

static double	GetDensityProbability (double r, double _time, double D)

static double	GetCumulativeProbability (double sTransform)

Public Attributes
std::vector< double >	fInverse

int	fNbins

double	fEpsilon

Detailed Description

Definition at line 70 of file G4DNASmoluchowskiDiffusion.hh.

Constructor & Destructor Documentation

G4DNASmoluchowskiDiffusion::G4DNASmoluchowskiDiffusion ( double epsilon = 1e-5 )

Definition at line 50 of file G4DNASmoluchowskiDiffusion.cc.

                                                                      :  fEpsilon(epsilon)
 {
   fNbins = (int) trunc(1/fEpsilon);
   // std::cout << "fNbins: " << fNbins << std::endl;
 #ifdef DNADEV
   assert(fNbins > 0);
 #endif
   fInverse.resize(fNbins+2); // trunc sous-estime + borne max a rajouter ==> 2
 
   // std::cout << "fInverse.capacity(): "<< fInverse.capacity() << std::endl;
 }

Here is the call graph for this function:

G4DNASmoluchowskiDiffusion::~G4DNASmoluchowskiDiffusion ( )

virtual

Definition at line 62 of file G4DNASmoluchowskiDiffusion.cc.

63 {

64 }

Member Function Documentation

static double G4DNASmoluchowskiDiffusion::ComputeDistance	(	double	sTransform,
		double	D,
		double	t
	)

inlinestatic

Definition at line 82 of file G4DNASmoluchowskiDiffusion.hh.

   {
     return sTransform * 2. * std::sqrt(D * t);
   }

Here is the caller graph for this function:

static double G4DNASmoluchowskiDiffusion::ComputeS	(	double	r,
		double	D,
		double	t
	)

inlinestatic

Definition at line 76 of file G4DNASmoluchowskiDiffusion.hh.

   {
     double sTransform = r / (2. * std::sqrt(D * t));
     return sTransform;
   }

static double G4DNASmoluchowskiDiffusion::ComputeTime	(	double	sTransform,
		double	D,
		double	r
	)

inlinestatic

Definition at line 87 of file G4DNASmoluchowskiDiffusion.hh.

   {
     return std::pow(r / sTransform, 2.) / (4. * D);
   }

Here is the call graph for this function:

Here is the caller graph for this function:

double G4DNASmoluchowskiDiffusion::EstimateCrossingTime	(	double	proba,
		double	distance,
		double	D
	)

inline

Definition at line 110 of file G4DNASmoluchowskiDiffusion.hh.

   {
     double sTransform = GetInverseProbability(proba);
     return ComputeTime(sTransform, D, distance);
   }

Here is the call graph for this function:

static double G4DNASmoluchowskiDiffusion::GetCumulativeProbability ( double sTransform )

inlinestatic

Definition at line 304 of file G4DNASmoluchowskiDiffusion.hh.

   {
     static double constant = 2./std::sqrt(3.141592653589793);
     return erfc(sTransform) + constant*sTransform*G4Exp(-sTransform*sTransform);
   }

Here is the call graph for this function:

Here is the caller graph for this function:

static double G4DNASmoluchowskiDiffusion::GetDensityProbability	(	double	r,
		double	_time,
		double	D
	)

inlinestatic

Definition at line 129 of file G4DNASmoluchowskiDiffusion.hh.

   {
     static double my_pi = 3.141592653589793;
     static double constant = 4.*my_pi/std::pow(4.*my_pi, 1.5);
     return r*r/std::pow(D * _time,1.5)*G4Exp(-r*r/(4. * D * _time))*constant;
   }

Here is the call graph for this function:

static double G4DNASmoluchowskiDiffusion::GetDifferential ( double sTransform )

inlinestatic

Definition at line 123 of file G4DNASmoluchowskiDiffusion.hh.

   {
     static double constant = -4./std::sqrt(3.141592653589793);
     return sTransform*sTransform*G4Exp(-sTransform*sTransform)*constant; // -4*sTransform*sTransform*exp(-sTransform*sTransform)/sqrt(3.141592653589793)
   }

Here is the call graph for this function:

Here is the caller graph for this function:

double G4DNASmoluchowskiDiffusion::GetInverseProbability ( double proba )

inline

Definition at line 310 of file G4DNASmoluchowskiDiffusion.hh.

   {
     size_t index_low = (size_t) trunc(proba/fEpsilon);
     
     if(index_low == 0) // assymptote en 0
     {
       index_low = 1;
       size_t index_up = 2;
       double low_y = fInverse[index_low];
       double up_y = fInverse[index_up];
       double low_x = index_low*fEpsilon;
       double up_x = proba+fEpsilon;
       double tangente = (low_y-up_y)/(low_x - up_x); // ou utiliser GetDifferential(proba) ?
       // double tangente = GetDifferential(proba);
       return low_y + tangente*(proba-low_x);
     }
 
     size_t index_up = index_low+1;
     if(index_low > fInverse.size()) return fInverse.back();
     double low_y = fInverse[index_low];
     double up_y = fInverse[index_up];
 
     double low_x = index_low*fEpsilon;
     double up_x = low_x+fEpsilon;
 
     if(up_x > 1) // P(1) = 0
     {
       up_x = 1;
       up_y = 0; // more general : fInverse.back()
     }
 
     double tangente = (low_y-up_y)/(low_x - up_x);
 
     return low_y + tangente*(proba-low_x);
   }

Here is the caller graph for this function:

double G4DNASmoluchowskiDiffusion::GetRandomDistance	(	double	_time,
		double	D
	)

inline

Definition at line 94 of file G4DNASmoluchowskiDiffusion.hh.

   {
     double proba = G4UniformRand();
 //    G4cout << "proba = " << proba << G4endl;
     double sTransform = GetInverseProbability(proba);
 //    G4cout << "sTransform = " << sTransform << G4endl;
     return ComputeDistance(sTransform, D, _time);
   }

Here is the call graph for this function:

double G4DNASmoluchowskiDiffusion::GetRandomTime	(	double	distance,
		double	D
	)

inline

Definition at line 103 of file G4DNASmoluchowskiDiffusion.hh.

   {
     double proba = G4UniformRand();
     double sTransform = GetInverseProbability(proba);
     return ComputeTime(sTransform, D, distance);
   }

Here is the call graph for this function:

void G4DNASmoluchowskiDiffusion::InitialiseInverseProbability ( double xmax = 3e28 )

inline

Definition at line 357 of file G4DNASmoluchowskiDiffusion.hh.

   {
     // x > x'
     // P'(x) = p(x') = lim(x->x') (P(x') - P(x))/(x'-x)
     // x'-x = (P(x') - P(x))/p(x')
     // x = x' - (P(x') - P(x))/p(x')
 
     // fInverse initialized in the constructor
 
     assert(fNbins !=0);
     PrepareReverseTable(0,xmax);
   }

Here is the call graph for this function:

double G4DNASmoluchowskiDiffusion::Plot	(	double *	x,
		double *
	)

inline

Definition at line 351 of file G4DNASmoluchowskiDiffusion.hh.

   {
     return GetDifferential(x[0]);
   }

Here is the call graph for this function:

double G4DNASmoluchowskiDiffusion::PlotInverse	(	double *	x,
		double *
	)

inline

Definition at line 346 of file G4DNASmoluchowskiDiffusion.hh.

   {
     return GetInverseProbability(x[0]);
   }

Here is the call graph for this function:

void G4DNASmoluchowskiDiffusion::PrepareReverseTable	(	double	xmin,
		double	xmax
	)

inline

Definition at line 263 of file G4DNASmoluchowskiDiffusion.hh.

   {
     double x = xmax;
     int index = 0;
     double nextProba = fEpsilon;
     double proposedX;
 
     BoundingBox boundingBox(xmin, xmax, fEpsilon*1e-5);
 
     while(index <= fNbins)
     // in case GetCumulativeProbability is exact (digitally speaking), replace with:
     // while(index <= fNbins+1)
     {
       nextProba = fEpsilon*index;
 
       double newProba = GetCumulativeProbability(x);
 
       if(boundingBox.Propose(x, newProba, nextProba, proposedX))
       {
         fInverse[index] = x;
         index++;
       }
       else
       {
         if(x == proposedX)
         {
           G4cout << "BREAK : x= " << x << G4endl;
           G4cout << "index= " << index << G4endl;
           G4cout << "nextProba= " << nextProba << G4endl;
           G4cout << "newProba= " << newProba << G4endl;
           abort();
         }
         x = proposedX;
       }
     }
     
     fInverse[fNbins+1] = 0; // P(1) = 0, because we want it exact !
     // Tips to improve the exactness: get an better value of pi, get better approximation of erf and exp, use long double instead of double
 //    boundingBox.Print();
   }

Here is the call graph for this function:

Here is the caller graph for this function:

Member Data Documentation

double G4DNASmoluchowskiDiffusion::fEpsilon

Definition at line 372 of file G4DNASmoluchowskiDiffusion.hh.

std::vector<double> G4DNASmoluchowskiDiffusion::fInverse

Definition at line 370 of file G4DNASmoluchowskiDiffusion.hh.

int G4DNASmoluchowskiDiffusion::fNbins

Definition at line 371 of file G4DNASmoluchowskiDiffusion.hh.

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

geant4.10.03.p01/source/processes/electromagnetic/dna/models/include/G4DNASmoluchowskiDiffusion.hh
geant4.10.03.p01/source/processes/electromagnetic/dna/models/src/G4DNASmoluchowskiDiffusion.cc

Classes

Public Member Functions

Static Public Member Functions

Public Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation