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mathGammaNormal.C
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1/// \file
2/// \ingroup tutorial_math
3/// \notebook
4/// Tutorial illustrating the use of TMath::GammaDist and TMath::LogNormal
5///
6/// \macro_image
7/// \macro_code
8///
9/// \author Anna Kreshuk
10
11void mathGammaNormal(){
12 TCanvas *myc = new TCanvas("c1","gamma and lognormal",10,10,600,800);
13 myc->Divide(1,2);
17
19 TF1 *fgamma = new TF1("fgamma", "TMath::GammaDist(x, [0], [1], [2])", 0, 10);
20 fgamma->SetParameters(0.5, 0, 1);
21 TF1 *f1 = fgamma->DrawCopy();
22 f1->SetMinimum(1e-5);
24 fgamma->SetParameters(1, 0, 1);
25 TF1 *f2 = fgamma->DrawCopy("same");
27 fgamma->SetParameters(2, 0, 1);
28 TF1 *f3 = fgamma->DrawCopy("same");
30 fgamma->SetParameters(5, 0, 1);
31 TF1 *f4 = fgamma->DrawCopy("same");
33 TLegend *legend1 = new TLegend(.2,.15,.5,.4);
34 legend1->AddEntry(f1,"gamma = 0.5 mu = 0 beta = 1","l");
35 legend1->AddEntry(f2,"gamma = 1 mu = 0 beta = 1","l");
36 legend1->AddEntry(f3,"gamma = 2 mu = 0 beta = 1","l");
37 legend1->AddEntry(f4,"gamma = 5 mu = 0 beta = 1","l");
38 legend1->Draw();
39
40 //TMath::LogNormal
44 TF1 *flog = new TF1("flog", "TMath::LogNormal(x, [0], [1], [2])", 0, 5);
45 flog->SetParameters(0.5, 0, 1);
46 TF1 *g1 = flog->DrawCopy();
47 g1->SetLineColor(kRed);
48 flog->SetParameters(1, 0, 1);
49 TF1 *g2 = flog->DrawCopy("same");
51 flog->SetParameters(2, 0, 1);
52 TF1 *g3 = flog->DrawCopy("same");
54 flog->SetParameters(5, 0, 1);
55 TF1 *g4 = flog->DrawCopy("same");
57 TLegend *legend2 = new TLegend(.2,.15,.5,.4);
58 legend2->AddEntry(g1,"sigma = 0.5 theta = 0 m = 1","l");
59 legend2->AddEntry(g2,"sigma = 1 theta = 0 m = 1","l");
60 legend2->AddEntry(g3,"sigma = 2 theta = 0 m = 1","l");
61 legend2->AddEntry(g4,"sigma = 5 theta = 0 m = 1","l");
62 legend2->Draw();
63}
64
#define e(i)
Definition RSha256.hxx:103
@ kRed
Definition Rtypes.h:66
@ kGreen
Definition Rtypes.h:66
@ kMagenta
Definition Rtypes.h:66
@ kBlue
Definition Rtypes.h:66
virtual void SetLineColor(Color_t lcolor)
Set the line color.
Definition TAttLine.h:40
The Canvas class.
Definition TCanvas.h:23
Definition TCanvas.cxx:719
1-Dim function class
Definition TF1.h:233
virtual void SetMinimum(Double_t minimum=-1111)
Set the minimum value along Y for this function In case the function is already drawn,...
Definition TF1.cxx:3407
virtual TF1 * DrawCopy(Option_t *option="") const
Draw a copy of this function with its current attributes.
Definition TF1.cxx:1365
virtual void SetParameters(const Double_t *params)
Definition TF1.h:672
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:320
void Draw(Option_t *option="") override
Draw this legend with its current attributes.
Definition TLegend.cxx:425
The most important graphics class in the ROOT system.