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1/// \file
2/// \ingroup tutorial_roofit
3/// \notebook -js
4/// Basic functionality: adding boxes with parameters, statistics to RooPlots, decorating with arrows, text etc...
6/// \macro_image
7/// \macro_output
8/// \macro_code
10/// \date July 2008
11/// \author Wouter Verkerke
13#include "RooRealVar.h"
14#include "RooDataSet.h"
15#include "RooGaussian.h"
16#include "TCanvas.h"
17#include "TAxis.h"
18#include "RooPlot.h"
19#include "TText.h"
20#include "TArrow.h"
21#include "TFile.h"
22using namespace RooFit;
26 // S e t u p m o d e l
27 // ---------------------
29 // Create observables
30 RooRealVar x("x", "x", -10, 10);
32 // Create Gaussian
33 RooRealVar sigma("sigma", "sigma", 1, 0.1, 10);
34 RooRealVar mean("mean", "mean", -3, -10, 10);
35 RooGaussian gauss("gauss", "gauss", x, mean, sigma);
37 // Generate a sample of 1000 events with sigma=3
38 RooDataSet *data = gauss.generate(x, 1000);
40 // Fit pdf to data
41 gauss.fitTo(*data);
43 // P l o t p . d . f a n d d a t a
44 // -------------------------------------
46 // Overlay projection of gauss on data
47 RooPlot *frame = x.frame(Name("xframe"), Title("RooPlot with decorations"), Bins(40));
48 data->plotOn(frame);
49 gauss.plotOn(frame);
51 // A d d b o x w i t h p d f p a r a m e t e r s
52 // -----------------------------------------------------
54 // Left edge of box starts at 55% of Xaxis)
55 gauss.paramOn(frame, Layout(0.55));
57 // A d d b o x w i t h d a t a s t a t i s t i c s
58 // -------------------------------------------------------
60 // X size of box is from 55% to 99% of Xaxis range, top of box is at 80% of Yaxis range)
61 data->statOn(frame, Layout(0.55, 0.99, 0.8));
63 // A d d t e x t a n d a r r o w
64 // -----------------------------------
66 // Add text to frame
67 TText *txt = new TText(2, 100, "Signal");
68 txt->SetTextSize(0.04);
69 txt->SetTextColor(kRed);
70 frame->addObject(txt);
72 // Add arrow to frame
73 TArrow *arrow = new TArrow(2, 100, -1, 50, 0.01, "|>");
74 arrow->SetLineColor(kRed);
75 arrow->SetFillColor(kRed);
76 arrow->SetLineWidth(3);
77 frame->addObject(arrow);
79 // P e r s i s t f r a m e w i t h a l l d e c o r a t i o n s i n R O O T f i l e
80 // ---------------------------------------------------------------------------------------------
82 TFile f("rf106_plotdecoration.root", "RECREATE");
83 frame->Write();
84 f.Close();
86 // To read back and plot frame with all decorations in clean root session do
87 // root> TFile f("rf106_plotdecoration.root") ;
88 // root> xframe->Draw() ;
90 new TCanvas("rf106_plotdecoration", "rf106_plotdecoration", 600, 600);
91 gPad->SetLeftMargin(0.15);
92 frame->GetYaxis()->SetTitleOffset(1.6);
93 frame->Draw();
#define f(i)
Definition: RSha256.hxx:104
@ kRed
Definition: Rtypes.h:66
#define gPad
Definition: TVirtualPad.h:287
virtual RooPlot * statOn(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())
Add a box with statistics information to the specified frame.
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
Definition: RooAbsData.cxx:547
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:33
Plain Gaussian p.d.f.
Definition: RooGaussian.h:24
A RooPlot is a plot frame and a container for graphics objects within that frame.
Definition: RooPlot.h:44
void addObject(TObject *obj, Option_t *drawOptions="", Bool_t invisible=kFALSE)
Add a generic object to this plot.
Definition: RooPlot.cxx:422
TAxis * GetYaxis() const
Definition: RooPlot.cxx:1263
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition: RooPlot.cxx:691
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:39
Draw all kinds of Arrows.
Definition: TArrow.h:29
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition: TAttAxis.cxx:293
virtual void SetTextColor(Color_t tcolor=1)
Set the text color.
Definition: TAttText.h:43
virtual void SetTextSize(Float_t tsize=1)
Set the text size.
Definition: TAttText.h:46
The Canvas class.
Definition: TCanvas.h:23
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format.
Definition: TFile.h:54
virtual Int_t Write(const char *name=0, Int_t option=0, Int_t bufsize=0)
Write this object to the current directory.
Definition: TObject.cxx:798
Base class for several text objects.
Definition: TText.h:22
RooCmdArg Layout(Double_t xmin, Double_t xmax=0.99, Double_t ymin=0.95)
RooCmdArg Bins(Int_t nbin)
const Double_t sigma
Double_t x[n]
Definition: legend1.C:17
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
static constexpr double gauss
const char * Name
Definition: TXMLSetup.cxx:67
const char * Title
Definition: TXMLSetup.cxx:68