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rf902_numgenconfig.C
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1 /// \file
2 /// \ingroup tutorial_roofit
3 /// \notebook -nodraw
4 /// Numeric algorithm tuning: configuration and customization of how MC sampling algorithms on specific pdfs are
5 /// executed
6 ///
7 /// \macro_output
8 /// \macro_code
9 ///
10 /// \date July 2008
11 /// \author Wouter Verkerke
12 
13 #include "RooRealVar.h"
14 #include "RooDataSet.h"
15 #include "RooConstVar.h"
16 #include "RooChebychev.h"
17 #include "TCanvas.h"
18 #include "TAxis.h"
19 #include "RooPlot.h"
20 #include "RooNumGenConfig.h"
21 #include "RooArgSet.h"
22 #include <iomanip>
23 using namespace RooFit;
24 
25 void rf902_numgenconfig()
26 {
27 
28  // 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
29  // ------------------------------------------------------------------
30 
31  // Example pdf for use below
32  RooRealVar x("x", "x", 0, 10);
33  RooChebychev model("model", "model", x, RooArgList(RooConst(0), RooConst(0.5), RooConst(-0.1)));
34 
35  // Change global strategy for 1D sampling problems without conditional observable
36  // (1st kFALSE) and without discrete observable (2nd kFALSE) from RooFoamGenerator,
37  // ( an interface to the TFoam MC generator with adaptive subdivisioning strategy ) to RooAcceptReject,
38  // a plain accept/reject sampling algorithm [ RooFit default before ROOT 5.23/04 ]
40 
41  // Generate 10Kevt using RooAcceptReject
42  RooDataSet *data_ar = model.generate(x, 10000, Verbose(kTRUE));
43  data_ar->Print();
44 
45  // 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
46  // -------------------------------------------------------------------------------------
47 
48  // Another possibility: associate custom MC sampling configuration as default for object 'model'
49  // The kTRUE argument will install a clone of the default configuration as specialized configuration
50  // for this model if none existed so far
51  model.specialGeneratorConfig(kTRUE)->method1D(kFALSE, kFALSE).setLabel("RooFoamGenerator");
52 
53  // 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
54  // ---------------------------------------------------------------------------------------
55 
56  // Adjust maximum number of steps of RooIntegrator1D in the global default configuration
57  RooAbsPdf::defaultGeneratorConfig()->getConfigSection("RooAcceptReject").setRealValue("nTrial1D", 2000);
58 
59  // Example of how to change the parameters of a numeric integrator
60  // (Each config section is a RooArgSet with RooRealVars holding real-valued parameters
61  // and RooCategories holding parameters with a finite set of options)
62  model.specialGeneratorConfig()->getConfigSection("RooFoamGenerator").setRealValue("chatLevel", 1);
63 
64  // Generate 10Kevt using RooFoamGenerator (FOAM verbosity increased with above chatLevel adjustment for illustration
65  // purposes)
66  RooDataSet *data_foam = model.generate(x, 10000, Verbose());
67  data_foam->Print();
68 }
RooArgSet::setRealValue
Bool_t setRealValue(const char *name, Double_t newVal=0, Bool_t verbose=kFALSE)
Set value of a RooAbsRealLValye stored in set with given name to newVal No error messages are printed...
Definition: RooArgSet.cxx:364
kTRUE
const Bool_t kTRUE
Definition: RtypesCore.h:91
RooChebychev.h
RooArgSet.h
RooChebychev
Chebychev polynomial p.d.f.
Definition: RooChebychev.h:25
RooArgList
RooArgList is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgList.h:21
RooAbsData::Print
virtual void Print(Option_t *options=0) const
Print TNamed name and title.
Definition: RooAbsData.h:191
x
Double_t x[n]
Definition: legend1.C:17
RooAbsPdf::defaultGeneratorConfig
static RooNumGenConfig * defaultGeneratorConfig()
Returns the default numeric MC generator configuration for all RooAbsReals.
Definition: RooAbsPdf.cxx:3572
TCanvas.h
RooDataSet.h
RooCategory::setLabel
virtual Bool_t setLabel(const char *label, bool printError=true) override
Set value by specifying the name of the desired state.
Definition: RooCategory.cxx:185
RooFit
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
Definition: RooCFunction1Binding.h:29
RooFit::Verbose
RooCmdArg Verbose(Bool_t flag=kTRUE)
Definition: RooGlobalFunc.cxx:189
kFALSE
const Bool_t kFALSE
Definition: RtypesCore.h:92
RooPlot.h
RooNumGenConfig::method1D
RooCategory & method1D(Bool_t cond, Bool_t cat)
Definition: RooNumGenConfig.cxx:180
RooRealVar.h
RooNumGenConfig::getConfigSection
const RooArgSet & getConfigSection(const char *name) const
Retrieve configuration information specific to integrator with given name.
Definition: RooNumGenConfig.cxx:295
rf902_numgenconfig
Definition: rf902_numgenconfig.py:1
RooConstVar.h
TAxis.h
RooNumGenConfig.h
RooDataSet
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:33
make_cnn_model.model
model
Definition: make_cnn_model.py:6
RooRealVar
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:37
RooFit::RooConst
RooConstVar & RooConst(Double_t val)
Definition: RooGlobalFunc.cxx:347