{
//
// To see the output of this macro, click begin_html <a href="gif/fitslicesy.gif" >here</a> end_html
// This macro illustrates how to use the TH1::FitSlicesY function
// It uses the TH2F histogram generated in macro hsimple.C
// It invokes FitSlicesY and draw the fitted "mean" and "sigma"
// in 2 sepate pads.
// This macro shows also how to annotate a picture, change
// some pad parameters.
//
gROOT->Reset();
// Change some default parameters in the current style
gStyle->SetLabelSize(0.06,"x");
gStyle->SetLabelSize(0.06,"y");
gStyle->SetFrameFillColor(38);
gStyle->SetTitleW(0.6);
gStyle->SetTitleH(0.1);
// Connect the input file and get the 2-d histogram in memory
TFile *hsimple = new TFile("hsimple.root");
TH2F *hpxpy = (TH2F*)hsimple->Get("hpxpy");
// Create a canvas and divide it
TCanvas *c1 = new TCanvas("c1","c1",700,500);
c1->SetFillColor(42);
c1->Divide(2,1);
c1->cd(1);
TPad *left = (TPad*)gPad;
left->Divide(1,2);
// Draw 2-d original histogram
left->cd(1);
gPad->SetTopMargin(0.12);
gPad->SetFillColor(33);
hpxpy->Draw();
hpxpy->GetXaxis()->SetLabelSize(0.06);
hpxpy->GetYaxis()->SetLabelSize(0.06);
hpxpy->SetMarkerColor(kYellow);
// Fit slices projected along Y fron bins in X [7,32]
hpxpy->FitSlicesY(0,0,0,20);
// Show fitted "mean" for each slice
left->cd(2);
gPad->SetFillColor(33);
hpxpy_0->Draw();
c1->cd(2);
TPad *right = (TPad*)gPad;
right->Divide(1,2);
right->cd(1);
gPad->SetTopMargin(0.12);
gPad->SetLeftMargin(0.15);
gPad->SetFillColor(33);
hpxpy_1->Draw();
// Show fitted "sigma" for each slice
right->cd(2);
gPad->SetTopMargin(0.12);
gPad->SetLeftMargin(0.15);
gPad->SetFillColor(33);
hpxpy_2->SetMinimum(0.8);
hpxpy_2->Draw();
//attributes
hpxpy_0->SetLineColor(kYellow);
hpxpy_1->SetLineColor(kYellow);
hpxpy_2->SetLineColor(kYellow);
hpxpy_0->SetMarkerColor(kRed);
hpxpy_1->SetMarkerColor(kRed);
hpxpy_2->SetMarkerColor(kRed);
hpxpy_0->SetMarkerStyle(21);
hpxpy_1->SetMarkerStyle(21);
hpxpy_2->SetMarkerStyle(21);
hpxpy_0->SetMarkerSize(0.6);
hpxpy_1->SetMarkerSize(0.6);
hpxpy_2->SetMarkerSize(0.6);
}