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Reference Guide
ratioplot2.C File Reference

Detailed Description

View in nbviewer Open in SWAN Example of a fit residual plot.

Creates a histogram filled with random numbers from a gaussian distribution and fits it with a standard gaussian function. The result is passed to the TRatioPlot constructor. Additionally, after calling TRatioPlot::Draw the upper and lower y axis titles are modified. Confidence interval bands are automatically drawn on the bottom (but can be disabled by draw option nobands.

void ratioplot2() {
auto c1 = new TCanvas("c1", "fit residual simple");
auto h1 = new TH1D("h1", "h1", 50, -5, 5);
h1->FillRandom("gaus", 2000);
h1->Fit("gaus", "0");
h1->GetXaxis()->SetTitle("x");
auto rp1 = new TRatioPlot(h1);
rp1->Draw();
rp1->GetLowerRefYaxis()->SetTitle("ratio");
rp1->GetUpperRefYaxis()->SetTitle("entries");
}
Author
Paul Gessinger

Definition in file ratioplot2.C.

TH1D
1-D histogram with a double per channel (see TH1 documentation)}
Definition: TH1.h:615
h1
TH1F * h1
Definition: legend1.C:5
gStyle
R__EXTERN TStyle * gStyle
Definition: TStyle.h:412
TNamed::SetTitle
virtual void SetTitle(const char *title="")
Set the title of the TNamed.
Definition: TNamed.cxx:164
TH1::FillRandom
virtual void FillRandom(const char *fname, Int_t ntimes=5000)
Fill histogram following distribution in function fname.
Definition: TH1.cxx:3444
TStyle::SetOptStat
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:1592
TCanvas
Definition: TCanvas.h:23
ratioplot2
Definition: ratioplot2.py:1
TRatioPlot
Definition: TRatioPlot.h:43
TH1::Fit
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:3807
TH1::GetXaxis
TAxis * GetXaxis()
Get the behaviour adopted by the object about the statoverflows. See EStatOverflows for more informat...
Definition: TH1.h:317
c1
return c1
Definition: legend1.C:41