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Reference Guide
Background_width.C
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1 /// \file
2 /// \ingroup tutorial_spectrum
3 /// \notebook
4 /// Example to illustrate the influence of the clipping window width on the
5 /// estimated background.
6 ///
7 /// \macro_image
8 /// \macro_code
9 ///
10 /// \authors Miroslav Morhac, Olivier Couet
11 
12 void Background_width() {
13  Int_t i;
14  const Int_t nbins = 1024;
15  Double_t xmin = 0;
17  Double_t source[nbins];
18  gROOT->ForceStyle();
19 
20  TString dir = gROOT->GetTutorialDir();
21  TString file = dir+"/spectrum/TSpectrum.root";
22  TFile *f = new TFile(file.Data());
23  TH1F *back = (TH1F*) f->Get("back1");
24  TH1F *d1 = new TH1F("d1","",nbins,xmin,xmax);
25  TH1F *d2 = new TH1F("d2","",nbins,xmin,xmax);
26  TH1F *d3 = new TH1F("d3","",nbins,xmin,xmax);
27 
28  back->GetXaxis()->SetRange(1,nbins);
29  back->SetTitle("Influence of clipping window width on the estimated background");
30  back->Draw("L");
31 
32  TSpectrum *s = new TSpectrum();
33 
34  for (i = 0; i < nbins; i++) source[i]=back->GetBinContent(i + 1);
38  for (i = 0; i < nbins; i++) d1->SetBinContent(i + 1,source[i]);
39  d1->SetLineColor(kRed);
40  d1->Draw("SAME L");
41 
42  for (i = 0; i < nbins; i++) source[i]=back->GetBinContent(i + 1);
46  for (i = 0; i < nbins; i++) d2->SetBinContent(i + 1,source[i]);
47  d2->SetLineColor(kOrange);
48  d2->Draw("SAME L");
49 
50  for (i = 0; i < nbins; i++) source[i]=back->GetBinContent(i + 1);
54  for (i = 0; i < nbins; i++) d3->SetBinContent(i + 1,source[i]);
55  d3->SetLineColor(kGreen);
56  d3->Draw("SAME L");
57 }
float xmin
Definition: THbookFile.cxx:93
Definition: Rtypes.h:56
THist< 1, float, THistStatContent, THistStatUncertainty > TH1F
Definition: THist.hxx:311
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format...
Definition: TFile.h:46
virtual TObject * Get(const char *namecycle)
Return pointer to object identified by namecycle.
#define gROOT
Definition: TROOT.h:375
Basic string class.
Definition: TString.h:129
tomato 1-D histogram with a float per channel (see TH1 documentation)}
Definition: TH1.h:551
int Int_t
Definition: RtypesCore.h:41
int nbins[3]
Definition: Rtypes.h:56
virtual void SetLineColor(Color_t lcolor)
Set the line color.
Definition: TAttLine.h:40
virtual void Draw(Option_t *option="")
Draw this histogram with options.
Definition: TH1.cxx:2851
virtual void SetBinContent(Int_t bin, Double_t content)
Set bin content see convention for numbering bins in TH1::GetBin In case the bin number is greater th...
Definition: TH1.cxx:8325
float xmax
Definition: THbookFile.cxx:93
const Bool_t kFALSE
Definition: RtypesCore.h:92
double f(double x)
double Double_t
Definition: RtypesCore.h:55
virtual TH1 * Background(const TH1 *hist, Int_t niter=20, Option_t *option="")
One-dimensional background estimation function.
Definition: TSpectrum.cxx:152
Advanced Spectra Processing.
Definition: TSpectrum.h:18
Definition: file.py:1
Definition: Rtypes.h:57
const char * Data() const
Definition: TString.h:347