TFoamSampler Class Reference

class implementing the ROOT::Math::DistSampler interface using FOAM for sampling arbitrary distributions.

Definition at line 39 of file TFoamSampler.h.

Public Member Functions
	TFoamSampler ()
	default constructor
	~TFoamSampler () override
	virtual destructor
TRandom *	GetRandom () override
	Get the random engine used by the sampler.
bool	Init (const char *="") override
	initialize the generators with the default options
bool	Init (const ROOT::Math::DistSamplerOptions &opt) override
	initialize the generators with the given options
bool	Sample (double *x) override
	sample one event in multi-dimension by filling the given array return false if sampling failed
bool	SampleBin (double prob, double &value, double *error=nullptr) override
	sample one bin given an estimated of the pdf in the bin (this can be function value at the center or its integral in the bin divided by the bin width) By default do not do random sample, just return the function values
void	SetFunction (const ROOT::Math::IGenFunction &func) override
	set the parent function distribution to use for random sampling (one dim case)
void	SetFunction (TF1 *pdf)
	set the Function using a TF1 pointer
void	SetRandom (TRandom *r) override
	Set the random engine to be used Needs to be called before Init to have effect.
void	SetSeed (unsigned int seed) override
	Set the random seed for the TRandom instances used by the sampler classes Needs to be called before Init to have effect.
Public Member Functions inherited from ROOT::Math::DistSampler
	DistSampler ()
	default constructor
virtual	~DistSampler ()
	virtual destructor
virtual bool	Generate (unsigned int nevt, const int *nbins, ROOT::Fit::BinData &data, bool extend=true, bool expErr=true)
	Generate a binned data set.
virtual bool	Generate (unsigned int nevt, double *data, bool eventRow=false)
	Generate a vector of events by filling the passed data vector.
bool	Generate (unsigned int nevt, int nbins, double xmin, double xmax, ROOT::Fit::BinData &data, bool extend=true, bool expErr=true)
	Same as before but passing the range in case of 1 dim data.
virtual bool	Generate (unsigned int nevt, ROOT::Fit::UnBinData &data)
	Generate a un-binned data set by filling the given data set object.
bool	HasParentPdf () const
	Check if there is a parent distribution defined.
unsigned int	NDim () const
	return the dimension of the parent distribution (and the data)
const ROOT::Math::IMultiGenFunction &	ParentPdf () const
	Get the parent distribution function (must be called after setting the function).
const double *	Sample ()
	Sample one event and return an array x with sample coordinates values.
virtual double	Sample1D ()
	Sample one event in one dimension.
virtual bool	SampleBins (unsigned int n, const double *prob, double *values, double *errors=nullptr)
	Sample a set of bins given a vector of probabilities Typically multinomial statistics will be used and the sum of the probabilities will be equal to the total number of events to be generated For sampling the bins independently, SampleBin should be used.
virtual void	SetArea (double)
	Set the normalization area of distribution.
virtual void	SetCdf (const ROOT::Math::IGenFunction &)
	Set usage of Cumulative of PDF.
virtual void	SetDPdf (const ROOT::Math::IGenFunction &)
	Set usage of Derivative of PDF.
virtual void	SetFunction (const ROOT::Math::IMultiGenFunction &func)
	set the parent function distribution to use for random sampling (multi-dim case)
template<class Function >
void	SetFunction (Function &func, unsigned int dim)
	set the parent function distribution to use for sampling (generic case)
virtual void	SetMode (const std::vector< double > &)
	Set the mode of the distribution (Multi-dim case).
virtual void	SetMode (double)
	Set the mode of the distribution (1D case).
void	SetRange (const double *xmin, const double *xmax)
	Set the range for all dimensions.
void	SetRange (const ROOT::Fit::DataRange &range)
	Set the range using the ROOT::Fit::DataRange class.
void	SetRange (const std::vector< double > &xmin, const std::vector< double > &xmax)
	Set the range for all dimensions (use std::vector)
void	SetRange (double xmin, double xmax, int icoord=0)
	Set the range in a given dimension.
virtual void	SetUseLogPdf (bool=true)
	Use the log of the provided pdf.

Private Attributes
TFoam *	fFoam
TFoamIntegrand *	fFoamDist
const ROOT::Math::IGenFunction *	fFunc1D

Additional Inherited Members
Protected Member Functions inherited from ROOT::Math::DistSampler
virtual void	DoSetDimension (unsigned int ndim)
virtual void	DoSetFunction (const ROOT::Math::IMultiGenFunction &func, bool copy)
bool	IsInitialized ()
const ROOT::Fit::DataRange &	PdfRange () const
	return the data range of the Pdf . Must be called after setting the function

#include <TFoamSampler.h>

Inheritance diagram for TFoamSampler:

Constructor & Destructor Documentation

TFoamSampler()

TFoamSampler::TFoamSampler

(

)

default constructor

Definition at line 82 of file TFoamSampler.cxx.

~TFoamSampler()

TFoamSampler::~TFoamSampler ( )

override

virtual destructor

Definition at line 92 of file TFoamSampler.cxx.

Member Function Documentation

GetRandom()

TRandom * TFoamSampler::GetRandom ( )

overridevirtual

Get the random engine used by the sampler.

Reimplemented from ROOT::Math::DistSampler.

Definition at line 172 of file TFoamSampler.cxx.

Init() [1/2]

bool TFoamSampler::Init ( const char *  = "" )

overridevirtual

initialize the generators with the default options

Reimplemented from ROOT::Math::DistSampler.

Definition at line 98 of file TFoamSampler.cxx.

Init() [2/2]

bool TFoamSampler::Init ( const ROOT::Math::DistSamplerOptions &  opt )

overridevirtual

initialize the generators with the given options

Reimplemented from ROOT::Math::DistSampler.

Definition at line 107 of file TFoamSampler.cxx.

Sample()

bool TFoamSampler::Sample ( double *  x )

overridevirtual

sample one event in multi-dimension by filling the given array return false if sampling failed

Implements ROOT::Math::DistSampler.

Definition at line 182 of file TFoamSampler.cxx.

SampleBin()

bool TFoamSampler::SampleBin ( double  prob, double &  value, double *  error = nullptr  )

overridevirtual

sample one bin given an estimated of the pdf in the bin (this can be function value at the center or its integral in the bin divided by the bin width) By default do not do random sample, just return the function values

Reimplemented from ROOT::Math::DistSampler.

Definition at line 195 of file TFoamSampler.cxx.

SetFunction() [1/2]

void TFoamSampler::SetFunction ( const ROOT::Math::IGenFunction &  func )

inlineoverridevirtual

set the parent function distribution to use for random sampling (one dim case)

Reimplemented from ROOT::Math::DistSampler.

Definition at line 54 of file TFoamSampler.h.

SetFunction() [2/2]

void TFoamSampler::SetFunction

(

TF1 *

pdf

)

set the Function using a TF1 pointer

Definition at line 156 of file TFoamSampler.cxx.

SetRandom()

void TFoamSampler::SetRandom ( TRandom *  r )

overridevirtual

Set the random engine to be used Needs to be called before Init to have effect.

Reimplemented from ROOT::Math::DistSampler.

Definition at line 161 of file TFoamSampler.cxx.

SetSeed()

void TFoamSampler::SetSeed ( unsigned int  seed )

overridevirtual

Set the random seed for the TRandom instances used by the sampler classes Needs to be called before Init to have effect.

Reimplemented from ROOT::Math::DistSampler.

Definition at line 166 of file TFoamSampler.cxx.

Member Data Documentation

fFoam

TFoam* TFoamSampler::fFoam

private

Definition at line 120 of file TFoamSampler.h.

fFoamDist

TFoamIntegrand* TFoamSampler::fFoamDist

private

Definition at line 121 of file TFoamSampler.h.

fFunc1D

const ROOT::Math::IGenFunction* TFoamSampler::fFunc1D

private

Definition at line 119 of file TFoamSampler.h.

Libraries for TFoamSampler:

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

• math/foam/inc/TFoamSampler.h
• math/foam/src/TFoamSampler.cxx