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Reference Guide
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 More...
 
virtual ~TFoamSampler ()
 virtual destructor More...
 
TRandomGetRandom ()
 Get the random engine used by the sampler. More...
 
bool Init (const char *="")
 initialize the generators with the default options More...
 
bool Init (const ROOT::Math::DistSamplerOptions &opt)
 initialize the generators with the given options More...
 
bool Sample (double *x)
 sample one event in multi-dimension by filling the given array return false if sampling failed More...
 
bool SampleBin (double prob, double &value, double *error=0)
 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 More...
 
void SetFunction (const ROOT::Math::IGenFunction &func)
 set the parent function distribution to use for random sampling (one dim case) More...
 
void SetFunction (TF1 *pdf)
 set the Function using a TF1 pointer More...
 
void SetRandom (TRandom *r)
 Set the random engine to be used Needs to be called before Init to have effect. More...
 
void SetSeed (unsigned int seed)
 Set the random seed for the TRandom instances used by the sampler classes Needs to be called before Init to have effect. More...
 
- Public Member Functions inherited from ROOT::Math::DistSampler
 DistSampler ()
 default constructor More...
 
virtual ~DistSampler ()
 virtual destructor More...
 
virtual bool Generate (unsigned int nevt, const int *nbins, ROOT::Fit::BinData &data, bool extend=true)
 generate a bin data set . More...
 
bool Generate (unsigned int nevt, int nbins, double xmin, double xmax, ROOT::Fit::BinData &data, bool extend=true)
 same as before but passing the range in case of 1 dim data More...
 
virtual bool Generate (unsigned int nevt, ROOT::Fit::UnBinData &data)
 generate a un-binned data sets (fill the given data set) if dataset has already data append to it More...
 
virtual TRandomGetRandom ()
 Get the random engine used by the sampler To be implemented by the derived classes who needs it Returns zero by default. More...
 
virtual bool Init (const char *="")
 initialize the generators with the given algorithm Implemented by derived classes who needs it (like UnuranSampler) If nothing is specified use default algorithm from DistSamplerOptions::SetDefaultAlgorithm More...
 
virtual bool Init (const DistSamplerOptions &opt)
 initialize the generators with the given option which my include the algorithm but also more if the method is re-impelmented by derived class The default implementation calls the above method passing just the algorithm name More...
 
unsigned int NDim () const
 return the dimension of the parent distribution (and the data) More...
 
const ROOT::Math::IMultiGenFunctionParentPdf () const
 get the parent distribution function (must be called after setting the function) More...
 
const doubleSample ()
 sample one event and rerturning array x with coordinates More...
 
virtual bool Sample (double *x)=0
 sample one event in multi-dimension by filling the given array return false if sampling failed More...
 
virtual double Sample1D ()
 sample one event in one dimension better implementation could be provided by the derived classes More...
 
virtual bool SampleBin (double prob, double &value, double *error=0)
 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 Typically Poisson statistics will be used More...
 
virtual bool SampleBins (unsigned int n, const double *prob, double *values, double *errors=0)
 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 indipendently, SampleBin should be used More...
 
virtual void SetArea (double)
 set the normalization area of distribution implemented by derived classes if needed More...
 
virtual void SetFunction (const ROOT::Math::IGenFunction &func)
 set the parent function distribution to use for random sampling (one dim case) More...
 
virtual void SetFunction (const ROOT::Math::IMultiGenFunction &func)
 set the parent function distribution to use for random sampling (multi-dim case) More...
 
template<class Function >
void SetFunction (Function &func, unsigned int dim)
 set the parent function distribution to use for sampling (generic case) More...
 
virtual void SetMode (double)
 set the mode of the distribution (could be useful to some methods) implemented by derived classes if needed More...
 
virtual void SetRandom (TRandom *)
 Set the random engine to be used To be implemented by the derived classes who provides random sampling. More...
 
void SetRange (const double *xmin, const double *xmax)
 set range for all dimensions More...
 
void SetRange (const ROOT::Fit::DataRange &range)
 set range using DataRange class More...
 
void SetRange (double xmin, double xmax, int icoord=0)
 set range in a given dimension More...
 
virtual void SetSeed (unsigned int)
 Set the random seed for the TRandom instances used by the sampler classes To be implemented by the derived classes who provides random sampling. More...
 

Private Attributes

TFoamfFoam
 
TFoamIntegrandfFoamDist
 
const ROOT::Math::IGenFunctionfFunc1D
 

Additional Inherited Members

- Protected Member Functions inherited from ROOT::Math::DistSampler
virtual void DoSetFunction (const ROOT::Math::IMultiGenFunction &func, bool copy)
 
bool IsInitialized ()
 
const ROOT::Fit::DataRangePdfRange () const
 return the data range of the Pdf . Must be called after setting the function More...
 

#include <TFoamSampler.h>

Inheritance diagram for TFoamSampler:
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Constructor & Destructor Documentation

◆ TFoamSampler()

TFoamSampler::TFoamSampler ( )

default constructor

Definition at line 82 of file TFoamSampler.cxx.

◆ ~TFoamSampler()

TFoamSampler::~TFoamSampler ( )
virtual

virtual destructor

Definition at line 92 of file TFoamSampler.cxx.

Member Function Documentation

◆ GetRandom()

TRandom * TFoamSampler::GetRandom ( )
virtual

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 *  = "")
virtual

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)
virtual

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)
virtual

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 = 0 
)
virtual

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)
inlinevirtual

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)
virtual

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)
virtual

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: