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1/// \file
2/// \ingroup tutorial_hist
3/// \notebook
4/// Example showing a fit residual plot, where the separation margin has been set to 0.
5/// The last label of the lower plot's y axis is hidden automatically.
7/// \macro_image
8/// \macro_code
10/// \author Paul Gessinger
12void ratioplot6() {
14 auto c1 = new TCanvas("c1", "fit residual simple");
15 gPad->SetFrameFillStyle(0);
16 auto h1 = new TH1D("h1", "h1", 50, -5, 5);
17 h1->FillRandom("gaus", 5000);
18 TFitResultPtr fitres = h1->Fit("gaus", "S0");
19 h1->Sumw2();
20 h1->GetXaxis()->SetTitle("x");
21 h1->GetYaxis()->SetTitle("y");
22 auto rp1 = new TRatioPlot(h1, "errfunc");
23 rp1->SetGraphDrawOpt("L");
24 rp1->SetSeparationMargin(0.0);
25 rp1->Draw();
26 rp1->GetLowerRefGraph()->SetMinimum(-2);
27 rp1->GetLowerRefGraph()->SetMaximum(2);
R__EXTERN TStyle * gStyle
Definition: TStyle.h:412
#define gPad
Definition: TVirtualPad.h:287
The Canvas class.
Definition: TCanvas.h:23
Provides an indirection to the TFitResult class and with a semantics identical to a TFitResult pointe...
Definition: TFitResultPtr.h:32
1-D histogram with a double per channel (see TH1 documentation)}
Definition: TH1.h:618
TAxis * GetXaxis()
Get the behaviour adopted by the object about the statoverflows. See EStatOverflows for more informat...
Definition: TH1.h:320
virtual void FillRandom(const char *fname, Int_t ntimes=5000, TRandom *rng=nullptr)
Fill histogram following distribution in function fname.
Definition: TH1.cxx:3525
virtual TFitResultPtr Fit(const char *formula, Option_t *option="", Option_t *goption="", Double_t xmin=0, Double_t xmax=0)
Fit histogram with function fname.
Definition: TH1.cxx:3892
TAxis * GetYaxis()
Definition: TH1.h:321
virtual void Sumw2(Bool_t flag=kTRUE)
Create structure to store sum of squares of weights.
Definition: TH1.cxx:8860
virtual void SetTitle(const char *title="")
Set the title of the TNamed.
Definition: TNamed.cxx:164
Class for displaying ratios, differences and fit residuals.
Definition: TRatioPlot.h:43
void SetOptStat(Int_t stat=1)
The type of information printed in the histogram statistics box can be selected via the parameter mod...
Definition: TStyle.cxx:1589
return c1
Definition: legend1.C:41
TH1F * h1
Definition: legend1.C:5