HistogramGenerator Class Reference

#include <HistogramGenerator.h>

Inheritance diagram for HistogramGenerator:

Public Member Functions
virtual double	function (double x)
	The probability density function implementation. More...
	HistogramGenerator (TH1 *histo)
	Constructor : initialization of the Random Generator. More...
virtual	~HistogramGenerator ()
	Default destructor. More...
Public Member Functions inherited from BaseNumericalRandomGenerator
	BaseNumericalRandomGenerator (double xmin=0., double xmax=1., int n=1000, int iter=6)
double	generate (RandomEngineAndDistribution const *) const
	The random generation according to function() More...
double	generateExp (RandomEngineAndDistribution const *) const
double	generateLin (RandomEngineAndDistribution const *) const
void	initialize ()
	The initialization (numerical integarion, inversion) More...
bool	setSubInterval (double x1, double x2)
	To shoot in a given interval. More...
virtual	~BaseNumericalRandomGenerator ()
	Default destructor. More...

Private Member Functions
double	ersatzt (double x)
	Gamma Function. More...

Private Attributes
TH1 *	myHisto
	Pointer to the histogram. More...
int	nbins
	n bins More...
TAxis *	theXaxis
	the axis More...

Additional Inherited Members
Protected Attributes inherited from BaseNumericalRandomGenerator
double	deltar
std::vector< double >	f
int	iter
int	n
double	rmin
std::vector< double >	sampling
double	xmax
double	xmin

Detailed Description

Definition at line 14 of file HistogramGenerator.h.

Constructor & Destructor Documentation

HistogramGenerator::HistogramGenerator ( TH1 *  histo )

inline

Constructor : initialization of the Random Generator.

Definition at line 19 of file HistogramGenerator.h.

References BaseNumericalRandomGenerator::initialize(), nbins, BaseNumericalRandomGenerator::xmax, and BaseNumericalRandomGenerator::xmin.

                                   :
     BaseNumericalRandomGenerator(histo->GetXaxis()->GetXmin(),
                  histo->GetXaxis()->GetXmax(),
                  100000,
                  3),
     myHisto(histo),
     theXaxis(histo->GetXaxis()),
     nbins(histo->GetXaxis()->GetNbins())
  {

    //    std::cout << "Old xmin/xmax = " << xmin << " " << xmax << std::endl;
    // Drop lowest and highest empty bins 
    double du = (xmax-xmin)/(float)nbins;
    // Restrict xmin to meaningful values
    while ( function(xmin) <= 0. ) xmin += du;
    // Restrict xmax to meaningful values
    while ( function(xmax) <= 0. ) xmax -= du;

    if ( xmin != histo->GetXaxis()->GetXmin() ) xmin -= du;
    if ( xmax != histo->GetXaxis()->GetXmax() ) xmax += du;

    //    std::cout << "New xmin/xmax = " << xmin << " " << xmax << std::endl;

    //    std::cout <<" Init " << std::endl;
    initialize();
  }

virtual HistogramGenerator::~HistogramGenerator ( )

inlinevirtual

Default destructor.

Definition at line 47 of file HistogramGenerator.h.

{}

Member Function Documentation

double HistogramGenerator::ersatzt ( double  x )

private

Gamma Function.

Definition at line 5 of file HistogramGenerator.cc.

References myHisto, nbins, and theXaxis.

Referenced by function().

{
  int ibin=theXaxis->FindBin(x);
  //  std::cout << x << " Bin " << ibin << std::endl;
  double x1=myHisto->GetBinLowEdge(ibin);
  double x2=x1+myHisto->GetBinWidth(ibin);
  double y1=myHisto->GetBinContent(ibin);  
  double y2;
  if(ibin<nbins)
    y2=myHisto->GetBinContent(ibin+1);
  else
    y2=y1;
  // std::cout << " X1 " << x1 <<" X2 " << x2 << " Y1 " <<y1 << " Y2 " << y2 << std::endl;
  return y2 + (y1-y2)*(x2-x)/(x2-x1);
}

virtual double HistogramGenerator::function ( double  x )

inlinevirtual

The probability density function implementation.

Implements BaseNumericalRandomGenerator.

Definition at line 50 of file HistogramGenerator.h.

References ersatzt(), and x.

{ return ersatzt(x); }

Member Data Documentation

TH1* HistogramGenerator::myHisto

private

Pointer to the histogram.

Definition at line 54 of file HistogramGenerator.h.

Referenced by ersatzt().

int HistogramGenerator::nbins

private

n bins

Definition at line 60 of file HistogramGenerator.h.

Referenced by python.rootplot.utilities.Hist::__init_TGraph(), python.rootplot.utilities.Hist::__len__(), python.rootplot.root2matplotlib.Hist::_prepare_xaxis(), python.rootplot.root2matplotlib.Hist::_prepare_yaxis(), python.rootplot.utilities.Hist::av_xerr(), python.rootplot.utilities.Hist::av_yerr(), python.rootplot.utilities.Hist::delete_bin(), python.rootplot.utilities.Hist::divide(), ersatzt(), HistogramGenerator(), python.rootplot.utilities.Hist::TGraph(), and python.rootplot.utilities.Hist::TH1F().

TAxis* HistogramGenerator::theXaxis

private

the axis

Definition at line 57 of file HistogramGenerator.h.

Referenced by ersatzt().