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rf401_importttreethx.C
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1 /// \file
2 /// \ingroup tutorial_roofit
3 /// \notebook -nodraw
4 ///
5 /// Data and categories: advanced options for importing data from ROOT TTree and THx histograms
6 ///
7 /// Basic import options are demonstrated in rf102_dataimport.C
8 ///
9 /// \macro_output
10 /// \macro_code
11 ///
12 /// \date 07/2008
13 /// \author Wouter Verkerke
14 
15 #include "RooRealVar.h"
16 #include "RooDataSet.h"
17 #include "RooDataHist.h"
18 #include "RooCategory.h"
19 #include "RooGaussian.h"
20 #include "RooConstVar.h"
21 #include "TCanvas.h"
22 #include "TAxis.h"
23 #include "RooPlot.h"
24 #include "TH1.h"
25 #include "TTree.h"
26 #include "TRandom.h"
27 #include <map>
28 
29 using namespace RooFit;
30 
31 TH1 *makeTH1(const char *name, Double_t mean, Double_t sigma);
32 TTree *makeTTree();
33 
34 void rf401_importttreethx()
35 {
36  // I m p o r t m u l t i p l e T H 1 i n t o a R o o D a t a H i s t
37  // --------------------------------------------------------------------------
38 
39  // Create thee ROOT TH1 histograms
40  TH1 *hh_1 = makeTH1("hh1", 0, 3);
41  TH1 *hh_2 = makeTH1("hh2", -3, 1);
42  TH1 *hh_3 = makeTH1("hh3", +3, 4);
43 
44  // Declare observable x
45  RooRealVar x("x", "x", -10, 10);
46 
47  // Create category observable c that serves as index for the ROOT histograms
48  RooCategory c("c", "c", {{"SampleA",0}, {"SampleB",1}, {"SampleC",2}});
49 
50  // Create a binned dataset that imports contents of all TH1 mapped by index category c
51  RooDataHist *dh = new RooDataHist("dh", "dh", x, Index(c), Import("SampleA", *hh_1), Import("SampleB", *hh_2),
52  Import("SampleC", *hh_3));
53  dh->Print();
54 
55  // Alternative constructor form for importing multiple histograms
56  std::map<std::string, TH1 *> hmap;
57  hmap["SampleA"] = hh_1;
58  hmap["SampleB"] = hh_2;
59  hmap["SampleC"] = hh_3;
60  RooDataHist *dh2 = new RooDataHist("dh", "dh", x, c, hmap);
61  dh2->Print();
62 
63  // I m p o r t i n g a T T r e e i n t o a R o o D a t a S e t w i t h c u t s
64  // -----------------------------------------------------------------------------------------
65 
66  TTree *tree = makeTTree();
67 
68  // Define observables y,z
69  RooRealVar y("y", "y", -10, 10);
70  RooRealVar z("z", "z", -10, 10);
71 
72  // Import only observables (y,z)
73  RooDataSet ds("ds", "ds", RooArgSet(x, y), Import(*tree));
74  ds.Print();
75 
76  // Import observables (x,y,z) but only event for which (y+z<0) is true
77  RooDataSet ds2("ds2", "ds2", RooArgSet(x, y, z), Import(*tree), Cut("y+z<0"));
78  ds2.Print();
79 
80  // I m p o r t i n g i n t e g e r T T r e e b r a n c h e s
81  // ---------------------------------------------------------------
82 
83  // Import integer tree branch as RooRealVar
84  RooRealVar i("i", "i", 0, 5);
85  RooDataSet ds3("ds3", "ds3", RooArgSet(i, x), Import(*tree));
86  ds3.Print();
87 
88  // Define category i
89  RooCategory icat("i", "i");
90  icat.defineType("State0", 0);
91  icat.defineType("State1", 1);
92 
93  // Import integer tree branch as RooCategory (only events with i==0 and i==1
94  // will be imported as those are the only defined states)
95  RooDataSet ds4("ds4", "ds4", RooArgSet(icat, x), Import(*tree));
96  ds4.Print();
97 
98  // I m p o r t m u l t i p l e R o o D a t a S e t s i n t o a R o o D a t a S e t
99  // ----------------------------------------------------------------------------------------
100 
101  // Create three RooDataSets in (y,z)
102  RooDataSet *dsA = (RooDataSet *)ds2.reduce(RooArgSet(x, y), "z<-5");
103  RooDataSet *dsB = (RooDataSet *)ds2.reduce(RooArgSet(x, y), "abs(z)<5");
104  RooDataSet *dsC = (RooDataSet *)ds2.reduce(RooArgSet(x, y), "z>5");
105 
106  // Create a dataset that imports contents of all the above datasets mapped by index category c
107  RooDataSet *dsABC = new RooDataSet("dsABC", "dsABC", RooArgSet(x, y), Index(c), Import("SampleA", *dsA),
108  Import("SampleB", *dsB), Import("SampleC", *dsC));
109 
110  dsABC->Print();
111 }
112 
113 TH1 *makeTH1(const char *name, Double_t mean, Double_t sigma)
114 {
115  // Create ROOT TH1 filled with a Gaussian distribution
116 
117  TH1D *hh = new TH1D(name, name, 100, -10, 10);
118  for (int i = 0; i < 1000; i++) {
119  hh->Fill(gRandom->Gaus(mean, sigma));
120  }
121  return hh;
122 }
123 
124 TTree *makeTTree()
125 {
126  // Create ROOT TTree filled with a Gaussian distribution in x and a uniform distribution in y
127 
128  TTree *tree = new TTree("tree", "tree");
129  Double_t *px = new Double_t;
130  Double_t *py = new Double_t;
131  Double_t *pz = new Double_t;
132  Int_t *pi = new Int_t;
133  tree->Branch("x", px, "x/D");
134  tree->Branch("y", py, "y/D");
135  tree->Branch("z", pz, "z/D");
136  tree->Branch("i", pi, "i/I");
137  for (int i = 0; i < 100; i++) {
138  *px = gRandom->Gaus(0, 3);
139  *py = gRandom->Uniform() * 30 - 15;
140  *pz = gRandom->Gaus(0, 5);
141  *pi = i % 3;
142  tree->Fill();
143  }
144  return tree;
145 }
c
#define c(i)
Definition: RSha256.hxx:119
TRandom::Gaus
virtual Double_t Gaus(Double_t mean=0, Double_t sigma=1)
Samples a random number from the standard Normal (Gaussian) Distribution with the given mean and sigm...
Definition: TRandom.cxx:263
tree
Definition: tree.py:1
TTree
Definition: TTree.h:79
RooGaussian.h
TH1D
1-D histogram with a double per channel (see TH1 documentation)}
Definition: TH1.h:615
TRandom.h
Int_t
int Int_t
Definition: RtypesCore.h:45
TRandom::Uniform
virtual Double_t Uniform(Double_t x1=1)
Returns a uniform deviate on the interval (0, x1).
Definition: TRandom.cxx:635
RooAbsData::Print
virtual void Print(Option_t *options=0) const
Print TNamed name and title.
Definition: RooAbsData.h:177
x
Double_t x[n]
Definition: legend1.C:17
TCanvas.h
TTree.h
RooDataSet.h
RooDataHist
Definition: RooDataHist.h:39
RooFit::Cut
RooCmdArg Cut(const char *cutSpec)
Definition: RooGlobalFunc.cxx:80
RooFit
Definition: RooCFunction1Binding.h:29
RooDataHist.h
RooPlot.h
TH1::Fill
virtual Int_t Fill(Double_t x)
Increment bin with abscissa X by 1.
Definition: TH1.cxx:3274
gRandom
R__EXTERN TRandom * gRandom
Definition: TRandom.h:62
RooCategory.h
y
Double_t y[n]
Definition: legend1.C:17
RooRealVar.h
RooConstVar.h
sigma
const Double_t sigma
Definition: h1analysisProxy.h:11
Double_t
double Double_t
Definition: RtypesCore.h:59
TGeant4Unit::pi
static constexpr double pi
Definition: TGeant4SystemOfUnits.h:73
RooCategory
Definition: RooCategory.h:27
RooAbsData::reduce
RooAbsData * reduce(const RooCmdArg &arg1, const RooCmdArg &arg2=RooCmdArg(), const RooCmdArg &arg3=RooCmdArg(), const RooCmdArg &arg4=RooCmdArg(), const RooCmdArg &arg5=RooCmdArg(), const RooCmdArg &arg6=RooCmdArg(), const RooCmdArg &arg7=RooCmdArg(), const RooCmdArg &arg8=RooCmdArg())
Create a reduced copy of this dataset.
Definition: RooAbsData.cxx:382
TAxis.h
TH1
Definition: TH1.h:57
name
char name[80]
Definition: TGX11.cxx:110
RooDataSet
Definition: RooDataSet.h:33
RooFit::Index
RooCmdArg Index(RooCategory &icat)
Definition: RooGlobalFunc.cxx:97
RooRealVar
Definition: RooRealVar.h:35
TH1.h
RooArgSet
Definition: RooArgSet.h:28
int
RooFit::Import
RooCmdArg Import(const char *state, TH1 &histo)
Definition: RooGlobalFunc.cxx:98