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Reference Guide
exampleTKDE.C File Reference

Detailed Description

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pict1_exampleTKDE.C.png
#include "TH1.h"
#include "TF1.h"
#include "TKDE.h"
#include "TCanvas.h"
/*#include "TStopwatch.h"*/
#include "TRandom.h"
#include "Math/DistFunc.h"
#include "TLegend.h"
// test TKDE
void exampleTKDE(int n = 1000) {
// generate some gaussian points
int nbin = 100;
double xmin = 0;
double xmax = 10;
TH1D * h1 = new TH1D("h1","h1",nbin,xmin,xmax);
// generate some points with bi- gaussian distribution
std::vector<double> data(n);
for (int i = 0; i < n; ++i) {
if (i < 0.4*n) {
data[i] = gRandom->Gaus(2,1);
h1->Fill(data[i]);
}
else {
data[i] = gRandom->Gaus(7,1.5);
h1->Fill(data[i]);
}
}
// scale histogram
h1->Scale(1./h1->Integral(),"width" );
h1->SetStats(false);
h1->SetTitle("Bi-Gaussian");
h1->Draw();
// drawn true normalized density
TF1 * f1 = new TF1("f1","0.4*ROOT::Math::normal_pdf(x,1,2)+0.6*ROOT::Math::normal_pdf(x,1.5,7)",xmin,xmax);
f1->Draw("SAME");
// create TKDE class
double rho = 1.0; //default value
TKDE * kde = new TKDE(n, &data[0], xmin,xmax, "", rho);
//kde->Draw("ConfidenceInterval@0.95 Same");
kde->Draw("SAME");
TLegend * legend = new TLegend(0.6,0.7,0.9,0.95);
legend->AddEntry(f1,"True function");
legend->AddEntry(kde->GetDrawnFunction(),"TKDE");
legend->AddEntry(kde->GetDrawnLowerFunction(),"TKDE - #sigma");
legend->AddEntry(kde->GetDrawnUpperFunction(),"TKDE + #sigma");
legend->Draw();
}
Authors
Lorenzo Moneta, Bartolomeu Rabacal (Dec 2010)

Definition in file exampleTKDE.C.