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normalDist.C File Reference

## Detailed Description

Tutorial illustrating the new statistical distributions functions (pdf, cdf and quantile)

#include "Math/DistFunc.h"
#include "TF1.h"
#include "TCanvas.h"
#include "TSystem.h"
#include "TLegend.h"
#include "TAxis.h"
void normalDist() {
TF1 *pdfunc = new TF1("pdf","ROOT::Math::normal_pdf(x, [0],[1])",-5,5);
TF1 *cdfunc = new TF1("cdf","ROOT::Math::normal_cdf(x, [0],[1])",-5,5);
TF1 *ccdfunc = new TF1("cdf_c","ROOT::Math::normal_cdf_c(x, [0])",-5,5);
TF1 *qfunc = new TF1("quantile","ROOT::Math::normal_quantile(x, [0])",0,1);
TF1 *cqfunc = new TF1("quantile_c","ROOT::Math::normal_quantile_c(x, [0])",0,1);
pdfunc->SetParameters(1.0,0.0); // set sigma to 1 and mean to zero
pdfunc->SetTitle("");
pdfunc->SetLineColor(kBlue);
pdfunc->GetXaxis()->SetLabelSize(0.06);
pdfunc->GetXaxis()->SetTitle("x");
pdfunc->GetXaxis()->SetTitleSize(0.07);
pdfunc->GetXaxis()->SetTitleOffset(0.55);
pdfunc->GetYaxis()->SetLabelSize(0.06);
cdfunc->SetParameters(1.0,0.0); // set sigma to 1 and mean to zero
cdfunc->SetTitle("");
cdfunc->SetLineColor(kRed);
cdfunc->GetXaxis()->SetLabelSize(0.06);
cdfunc->GetXaxis()->SetTitle("x");
cdfunc->GetXaxis()->SetTitleSize(0.07);
cdfunc->GetXaxis()->SetTitleOffset(0.55);
cdfunc->GetYaxis()->SetLabelSize(0.06);
cdfunc->GetYaxis()->SetTitle("p");
cdfunc->GetYaxis()->SetTitleSize(0.07);
cdfunc->GetYaxis()->SetTitleOffset(0.55);
ccdfunc->SetParameters(1.0,0.0); // set sigma to 1 and mean to zero
ccdfunc->SetTitle("");
ccdfunc->SetLineColor(kGreen);
qfunc->SetParameter(0, 1.0); // set sigma to 1
qfunc->SetTitle("");
qfunc->SetLineColor(kRed);
qfunc->SetNpx(1000); // to get more precision for p close to 0 or 1
qfunc->GetXaxis()->SetLabelSize(0.06);
qfunc->GetXaxis()->SetTitle("p");
qfunc->GetYaxis()->SetLabelSize(0.06);
qfunc->GetXaxis()->SetTitleSize(0.07);
qfunc->GetXaxis()->SetTitleOffset(0.55);
qfunc->GetYaxis()->SetTitle("x");
qfunc->GetYaxis()->SetTitleSize(0.07);
qfunc->GetYaxis()->SetTitleOffset(0.55);
cqfunc->SetParameter(0, 1.0); // set sigma to 1
cqfunc->SetTitle("");
cqfunc->SetLineColor(kGreen);
cqfunc->SetNpx(1000);
TCanvas * c1 = new TCanvas("c1","Normal Distributions",100,10,600,800);
c1->Divide(1,3);
c1->cd(1);
pdfunc->Draw();
TLegend *legend1 = new TLegend(0.583893,0.601973,0.885221,0.854151);
legend1->Draw();
c1->cd(2);
cdfunc->Draw();
ccdfunc->Draw("same");
TLegend *legend2 = new TLegend(0.585605,0.462794,0.886933,0.710837);
legend2->Draw();
c1->cd(3);
qfunc->Draw();
cqfunc->Draw("same");
TLegend *legend3 = new TLegend(0.315094,0.633668,0.695179,0.881711);
legend3->Draw();
}
@ kRed
Definition Rtypes.h:66
@ kGreen
Definition Rtypes.h:66
@ kBlue
Definition Rtypes.h:66
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition TAttAxis.cxx:293
virtual void SetLabelSize(Float_t size=0.04)
Set size of axis labels.
Definition TAttAxis.cxx:203
virtual void SetTitleSize(Float_t size=0.04)
Set size of axis title.
Definition TAttAxis.cxx:303
virtual void SetLineColor(Color_t lcolor)
Set the line color.
Definition TAttLine.h:40
The Canvas class.
Definition TCanvas.h:23
1-Dim function class
Definition TF1.h:213
TAxis * GetYaxis() const
Get y axis of the function.
Definition TF1.cxx:2399
virtual void SetTitle(const char *title="")
Set function title if title has the form "fffffff;xxxx;yyyy", it is assumed that the function title i...
Definition TF1.cxx:3562
virtual void SetNpx(Int_t npx=100)
Set the number of points used to draw the function.
Definition TF1.cxx:3446
virtual void Draw(Option_t *option="")
Draw this function with its current attributes.
Definition TF1.cxx:1322
virtual void SetParameters(const Double_t *params)
Definition TF1.h:644
virtual void SetParameter(Int_t param, Double_t value)
Definition TF1.h:634
TAxis * GetXaxis() const
Get x axis of the function.
Definition TF1.cxx:2388
This class displays a legend box (TPaveText) containing several legend entries.
Definition TLegend.h:23
TLegendEntry * AddEntry(const TObject *obj, const char *label="", Option_t *option="lpf")
Add a new entry to this legend.
Definition TLegend.cxx:330
virtual void Draw(Option_t *option="")
Draw this legend with its current attributes.
Definition TLegend.cxx:423
virtual void SetTitle(const char *title="")
Set the title of the TNamed.
Definition TNamed.cxx:164
return c1
Definition legend1.C:41

Definition in file normalDist.C.