Logo ROOT  
Reference Guide
RooChi2MCSModule.cxx
Go to the documentation of this file.
1/*****************************************************************************
2 * Project: RooFit *
3 * Package: RooFitCore *
4 * @(#)root/roofitcore:$Id$
5 * Authors: *
6 * WV, Wouter Verkerke, UC Santa Barbara, verkerke@slac.stanford.edu *
7 * DK, David Kirkby, UC Irvine, dkirkby@uci.edu *
8 * *
9 * Copyright (c) 2000-2005, Regents of the University of California *
10 * and Stanford University. All rights reserved. *
11 * *
12 * Redistribution and use in source and binary forms, *
13 * with or without modification, are permitted according to the terms *
14 * listed in LICENSE (http://roofit.sourceforge.net/license.txt) *
15 *****************************************************************************/
16
17/** \class RooChi2MCSModule
18 \ingroup Roofit
19
20RooChi2MCSModule is an add-on module to RooMCStudy that
21calculates the chi-squared of fitted p.d.f with respect to a binned
22version of the data. For each fit the chi-squared, the reduced chi-squared
23the number of degrees of freedom and the probability of the chi-squared
24is store in the summary dataset.
25**/
26
27#include "Riostream.h"
28
29#include "RooAbsPdf.h"
30#include "RooDataSet.h"
31#include "RooRealVar.h"
32#include "RooFitResult.h"
33#include "RooChi2MCSModule.h"
34#include "RooMsgService.h"
35#include "RooDataHist.h"
36#include "TMath.h"
37#include "RooGlobalFunc.h"
38
39using namespace std;
40
42
43////////////////////////////////////////////////////////////////////////////////
44
46 RooAbsMCStudyModule("RooChi2MCSModule","RooChi2Module"),
47 _data(0), _chi2(0), _ndof(0), _chi2red(0), _prob(0)
48
49{
50 // Constructor of module
51}
52
53////////////////////////////////////////////////////////////////////////////////
54/// Copy constructor
55
58 _data(0), _chi2(0), _ndof(0), _chi2red(0), _prob(0)
59{
60}
61
62////////////////////////////////////////////////////////////////////////////////
63/// Destructor
64
66{
67 if (_chi2) {
68 delete _chi2 ;
69 }
70 if (_ndof) {
71 delete _ndof ;
72 }
73 if (_chi2red) {
74 delete _chi2red ;
75 }
76 if (_prob) {
77 delete _prob ;
78 }
79 if (_data) {
80 delete _data ;
81 }
82}
83
84////////////////////////////////////////////////////////////////////////////////
85/// Initialize module after attachment to RooMCStudy object
86
88{
89 // Construct variable that holds -log(L) fit with null hypothesis for given parameter
90 _chi2 = new RooRealVar("chi2","chi^2",0) ;
91 _ndof = new RooRealVar("ndof","number of degrees of freedom",0) ;
92 _chi2red = new RooRealVar("chi2red","reduced chi^2",0) ;
93 _prob = new RooRealVar("prob","prob(chi2,ndof)",0) ;
94
95 // Create new dataset to be merged with RooMCStudy::fitParDataSet
96 _data = new RooDataSet("Chi2Data","Additional data for Chi2 study",RooArgSet(*_chi2,*_ndof,*_chi2red,*_prob)) ;
97
98 return true ;
99}
100
101////////////////////////////////////////////////////////////////////////////////
102/// Initialize module at beginning of RooCMStudy run
103
105{
106 _data->reset() ;
107 return true ;
108}
109
110////////////////////////////////////////////////////////////////////////////////
111/// Return auxiliary dataset with results of chi2 analysis
112/// calculations of this module so that it is merged with
113/// RooMCStudy::fitParDataSet() by RooMCStudy
114
116{
117 return _data ;
118}
119
120////////////////////////////////////////////////////////////////////////////////
121/// Bin dataset and calculate chi2 of p.d.f w.r.t binned dataset
122
124{
126 RooDataHist* binnedData = dynamic_cast<RooDataHist*>(data) ;
127 bool deleteData(false) ;
128 if (!binnedData) {
129 deleteData = true ;
130 binnedData = ((RooDataSet*)data)->binnedClone() ;
131 }
132
133 std::unique_ptr<RooAbsReal> chi2Var{fitModel()->createChi2(*binnedData,RooFit::Extended(extendedGen()),RooFit::DataError(RooAbsData::SumW2))};
134
135 RooArgSet* floatPars = (RooArgSet*) fitParams()->selectByAttrib("Constant",false) ;
136
137 _chi2->setVal(chi2Var->getVal()) ;
138 _ndof->setVal(binnedData->numEntries()-floatPars->getSize()-1) ;
140 _prob->setVal(TMath::Prob(_chi2->getVal(),static_cast<int>(_ndof->getVal()))) ;
141
143
144 if (deleteData) {
145 delete binnedData ;
146 }
147 delete floatPars ;
148
149 return true ;
150}
#define ClassImp(name)
Definition: Rtypes.h:375
Option_t Option_t TPoint TPoint const char GetTextMagnitude GetFillStyle GetLineColor GetLineWidth GetMarkerStyle GetTextAlign GetTextColor GetTextSize void data
RooAbsCollection * selectByAttrib(const char *name, bool value) const
Create a subset of the current collection, consisting only of those elements with the specified attri...
Int_t getSize() const
Return the number of elements in the collection.
RooAbsData is the common abstract base class for binned and unbinned datasets.
Definition: RooAbsData.h:61
virtual void reset()
Definition: RooAbsData.cxx:381
virtual Int_t numEntries() const
Return number of entries in dataset, i.e., count unweighted entries.
Definition: RooAbsData.cxx:374
RooAbsMCStudyModule is a base class for add-on modules to RooMCStudy that can perform additional calc...
bool extendedGen()
If true extended mode generation is requested.
RooAbsData * genSample()
Return generate sample.
RooAbsPdf * fitModel()
Return fit model.
RooArgSet * fitParams()
Return current value of parameters of fit model.
RooAbsReal * createChi2(RooDataHist &data, const RooCmdArg &arg1=RooCmdArg::none(), const RooCmdArg &arg2=RooCmdArg::none(), const RooCmdArg &arg3=RooCmdArg::none(), const RooCmdArg &arg4=RooCmdArg::none(), const RooCmdArg &arg5=RooCmdArg::none(), const RooCmdArg &arg6=RooCmdArg::none(), const RooCmdArg &arg7=RooCmdArg::none(), const RooCmdArg &arg8=RooCmdArg::none()) override
Create a from a histogram and this function.
Definition: RooAbsPdf.cxx:1789
double getVal(const RooArgSet *normalisationSet=nullptr) const
Evaluate object.
Definition: RooAbsReal.h:104
RooArgSet is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgSet.h:56
RooChi2MCSModule is an add-on module to RooMCStudy that calculates the chi-squared of fitted p....
~RooChi2MCSModule() override
Destructor.
RooRealVar * _chi2red
bool processAfterFit(Int_t) override
Bin dataset and calculate chi2 of p.d.f w.r.t binned dataset.
RooRealVar * _ndof
bool initializeRun(Int_t) override
Initialize module at beginning of RooCMStudy run.
RooRealVar * _chi2
RooRealVar * _prob
bool initializeInstance() override
Initialize module after attachment to RooMCStudy object.
RooDataSet * finalizeRun() override
Return auxiliary dataset with results of chi2 analysis calculations of this module so that it is merg...
RooDataSet * _data
The RooDataHist is a container class to hold N-dimensional binned data.
Definition: RooDataHist.h:39
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:55
void add(const RooArgSet &row, double weight=1.0, double weightError=0.0) override
Add one ore more rows of data.
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:40
void setVal(double value) override
Set value of variable to 'value'.
Definition: RooRealVar.cxx:254
RooCmdArg DataError(Int_t)
RooCmdArg Extended(bool flag=true)
Double_t Prob(Double_t chi2, Int_t ndf)
Computation of the probability for a certain Chi-squared (chi2) and number of degrees of freedom (ndf...
Definition: TMath.cxx:637