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"# pdf006_Gamma_LogNormal\n",
"Tutorial illustrating the use of TMath::GammaDist and TMath::LogNormal\n",
"\n",
"\n",
"\n",
"\n",
"**Author:** Anna Kreshuk \n",
"This notebook tutorial was automatically generated with ROOTBOOK-izer from the macro found in the ROOT repository on Tuesday, May 19, 2026 at 08:26 PM."
]
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"TCanvas *myc = new TCanvas(\"c1\",\"gamma and lognormal\",10,10,600,800);\n",
"myc->Divide(1,2);\n",
"TPad *pad1 = (TPad *)myc->cd(1);\n",
"pad1->SetLogy();\n",
"pad1->SetGrid();"
]
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"cell_type": "markdown",
"id": "1d99ca68",
"metadata": {},
"source": [
"TMath::GammaDist"
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"TF1 *fgamma = new TF1(\"fgamma\", \"TMath::GammaDist(x, [0], [1], [2])\", 0, 10);\n",
"fgamma->SetParameters(0.5, 0, 1);\n",
"TF1 *f1 = fgamma->DrawCopy();\n",
"f1->SetMinimum(1e-5);\n",
"f1->SetLineColor(kRed);\n",
"fgamma->SetParameters(1, 0, 1);\n",
"TF1 *f2 = fgamma->DrawCopy(\"same\");\n",
"f2->SetLineColor(kGreen);\n",
"fgamma->SetParameters(2, 0, 1);\n",
"TF1 *f3 = fgamma->DrawCopy(\"same\");\n",
"f3->SetLineColor(kBlue);\n",
"fgamma->SetParameters(5, 0, 1);\n",
"TF1 *f4 = fgamma->DrawCopy(\"same\");\n",
"f4->SetLineColor(kMagenta);\n",
"TLegend *legend1 = new TLegend(.2,.15,.5,.4);\n",
"legend1->AddEntry(f1,\"gamma = 0.5 mu = 0 beta = 1\",\"l\");\n",
"legend1->AddEntry(f2,\"gamma = 1 mu = 0 beta = 1\",\"l\");\n",
"legend1->AddEntry(f3,\"gamma = 2 mu = 0 beta = 1\",\"l\");\n",
"legend1->AddEntry(f4,\"gamma = 5 mu = 0 beta = 1\",\"l\");\n",
"legend1->Draw();"
]
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"cell_type": "markdown",
"id": "af589d68",
"metadata": {},
"source": [
"TMath::LogNormal"
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"source": [
"TPad *pad2 = (TPad *)myc->cd(2);\n",
"pad2->SetLogy();\n",
"pad2->SetGrid();\n",
"TF1 *flog = new TF1(\"flog\", \"TMath::LogNormal(x, [0], [1], [2])\", 0, 5);\n",
"flog->SetParameters(0.5, 0, 1);\n",
"TF1 *g1 = flog->DrawCopy();\n",
"g1->SetLineColor(kRed);\n",
"flog->SetParameters(1, 0, 1);\n",
"TF1 *g2 = flog->DrawCopy(\"same\");\n",
"g2->SetLineColor(kGreen);\n",
"flog->SetParameters(2, 0, 1);\n",
"TF1 *g3 = flog->DrawCopy(\"same\");\n",
"g3->SetLineColor(kBlue);\n",
"flog->SetParameters(5, 0, 1);\n",
"TF1 *g4 = flog->DrawCopy(\"same\");\n",
"g4->SetLineColor(kMagenta);\n",
"TLegend *legend2 = new TLegend(.2,.15,.5,.4);\n",
"legend2->AddEntry(g1,\"sigma = 0.5 theta = 0 m = 1\",\"l\");\n",
"legend2->AddEntry(g2,\"sigma = 1 theta = 0 m = 1\",\"l\");\n",
"legend2->AddEntry(g3,\"sigma = 2 theta = 0 m = 1\",\"l\");\n",
"legend2->AddEntry(g4,\"sigma = 5 theta = 0 m = 1\",\"l\");\n",
"legend2->Draw();"
]
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"id": "893b3eb2",
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"source": [
"Draw all canvases "
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