ROOT   Reference Guide
rf203_ranges.C
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1/// \file
2/// \ingroup tutorial_roofit
3/// \notebook -js
4///
5/// Addition and convolution: fitting and plotting in sub ranges
6///
7/// \macro_image
8/// \macro_output
9/// \macro_code
10///
11/// \date 07/2008
12/// \author Wouter Verkerke
13
14#include "RooRealVar.h"
15#include "RooDataSet.h"
16#include "RooGaussian.h"
17#include "RooConstVar.h"
18#include "RooPolynomial.h"
20#include "RooFitResult.h"
21#include "RooPlot.h"
22#include "TCanvas.h"
23#include "TAxis.h"
24#include "TH1.h"
25using namespace RooFit;
26
27void rf203_ranges()
28{
29 // S e t u p m o d e l
30 // ---------------------
31
32 // Construct observables x
33 RooRealVar x("x", "x", -10, 10);
34
35 // Construct gaussx(x,mx,1)
36 RooRealVar mx("mx", "mx", 0, -10, 10);
37 RooGaussian gx("gx", "gx", x, mx, RooConst(1));
38
39 // Construct px = 1 (flat in x)
40 RooPolynomial px("px", "px", x);
41
42 // Construct model = f*gx + (1-f)px
43 RooRealVar f("f", "f", 0., 1.);
44 RooAddPdf model("model", "model", RooArgList(gx, px), f);
45
46 // Generated 10000 events in (x,y) from p.d.f. model
47 RooDataSet *modelData = model.generate(x, 10000);
48
49 // F i t f u l l r a n g e
50 // ---------------------------
51
52 // Fit p.d.f to all data
53 RooFitResult *r_full = model.fitTo(*modelData, Save(kTRUE));
54
55 // F i t p a r t i a l r a n g e
56 // ----------------------------------
57
58 // Define "signal" range in x as [-3,3]
59 x.setRange("signal", -3, 3);
60
61 // Fit p.d.f only to data in "signal" range
62 RooFitResult *r_sig = model.fitTo(*modelData, Save(kTRUE), Range("signal"));
63
64 // P l o t / p r i n t r e s u l t s
65 // ---------------------------------------
66
67 // Make plot frame in x and add data and fitted model
68 RooPlot *frame = x.frame(Title("Fitting a sub range"));
69 modelData->plotOn(frame);
70 model.plotOn(frame, Range("Full"), LineStyle(kDashed), LineColor(kRed)); // Add shape in full ranged dashed
71 model.plotOn(frame); // By default only fitted range is shown
72
73 // Print fit results
74 cout << "result of fit on all data " << endl;
75 r_full->Print();
76 cout << "result of fit in in signal region (note increased error on signal fraction)" << endl;
77 r_sig->Print();
78
79 // Draw frame on canvas
80 new TCanvas("rf203_ranges", "rf203_ranges", 600, 600);
82 frame->GetYaxis()->SetTitleOffset(1.4);
83 frame->Draw();
84
85 return;
86}
#define f(i)
Definition: RSha256.hxx:104
const Bool_t kTRUE
Definition: RtypesCore.h:89
@ kRed
Definition: Rtypes.h:64
@ kDashed
Definition: TAttLine.h:48
virtual RooPlot * plotOn(RooPlot *frame, 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()) const
Calls RooPlot* plotOn(RooPlot* frame, const RooLinkedList& cmdList) const ;.
Definition: RooAbsData.cxx:546
RooAddPdf is an efficient implementation of a sum of PDFs of the form.
RooArgList is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgList.h:21
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:33
RooFitResult is a container class to hold the input and output of a PDF fit to a dataset.
Definition: RooFitResult.h:40
virtual void Print(Option_t *options=0) const
Print TNamed name and title.
Definition: RooFitResult.h:66
Plain Gaussian p.d.f.
Definition: RooGaussian.h:25
A RooPlot is a plot frame and a container for graphics objects within that frame.
Definition: RooPlot.h:44
TAxis * GetYaxis() const
Definition: RooPlot.cxx:1277
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition: RooPlot.cxx:712
RooPolynomial implements a polynomial p.d.f of the form.
Definition: RooPolynomial.h:28
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:35
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition: TAttAxis.cxx:294
The Canvas class.
Definition: TCanvas.h:27
RooConstVar & RooConst(Double_t val)
RooCmdArg Save(Bool_t flag=kTRUE)
RooCmdArg LineColor(Color_t color)
RooCmdArg LineStyle(Style_t style)
Double_t x[n]
Definition: legend1.C:17
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
const char * Title
Definition: TXMLSetup.cxx:67
Ta Range(0, 0, 1, 1)