doc/v606/rf902__numgenconfig_8C.html

#ifndef __CINT__

#include "RooGlobalFunc.h"

#endif

#include "RooRealVar.h"

#include "RooDataSet.h"

#include "RooConstVar.h"

#include "RooChebychev.h"

#include "TCanvas.h"

#include "TAxis.h"

#include "RooPlot.h"

#include "RooNumGenConfig.h"

#include "RooArgSet.h"

#include <iomanip>

using namespace RooFit ;


void rf902_numgenconfig()

{


  // A d j u s t   g l o b a l   MC   s a m p l i n g   s t r a t e g y

  // ------------------------------------------------------------------


  // Example p.d.f. for use below

  RooRealVar x("x","x",0,10) ;

  RooChebychev model("model","model",x,RooArgList(RooConst(0),RooConst(0.5),RooConst(-0.1))) ;


  // Change global strategy for 1D sampling problems without conditional observable

  // (1st kFALSE) and without discrete observable (2nd kFALSE) from RooFoamGenerator,

  // ( an interface to the TFoam MC generator with adaptive subdivisioning strategy ) to RooAcceptReject,

  // a plain accept/reject sampling algorithm [ RooFit default before ROOT 5.23/04 ]

  RooAbsPdf::defaultGeneratorConfig()->method1D(kFALSE,kFALSE).setLabel("RooAcceptReject") ;


  // Generate 10Kevt using RooAcceptReject

  RooDataSet* data_ar = model.generate(x,10000,Verbose(kTRUE)) ;

  data_ar->Print() ;


  // A d j u s t i n g   d e f a u l t   c o n f i g   f o r   a   s p e c i f i c   p d f

  // -------------------------------------------------------------------------------------


  // Another possibility: associate custom MC sampling configuration as default for object 'model'

  // The kTRUE argument will install a clone of the default configuration as specialized configuration

  // for this model if none existed so far

  model.specialGeneratorConfig(kTRUE)->method1D(kFALSE,kFALSE).setLabel("RooFoamGenerator") ;


  // A d j u s t i n g   p a r a m e t e r s   o f   a   s p e c i f i c   t e c h n i q u e

  // ---------------------------------------------------------------------------------------


  // Adjust maximum number of steps of RooIntegrator1D in the global default configuration

  RooAbsPdf::defaultGeneratorConfig()->getConfigSection("RooAcceptReject").setRealValue("nTrial1D",2000) ;


  // Example of how to change the parameters of a numeric integrator

  // (Each config section is a RooArgSet with RooRealVars holding real-valued parameters

  //  and RooCategories holding parameters with a finite set of options)

  model.specialGeneratorConfig()->getConfigSection("RooFoamGenerator").setRealValue("chatLevel",1) ;


  // Generate 10Kevt using RooFoamGenerator (FOAM verbosity increased with above chatLevel adjustment for illustration purposes)

  RooDataSet* data_foam = model.generate(x,10000,Verbose()) ;

  data_foam->Print() ;


}