ROOT_528-00b_version: tutorials/hist/hbars.C Source File

00001 // Example of bar charts with 1-d histograms
00002 // Author: Rene Brun
00003 {
00004    TString dir = gSystem->UnixPathName(gInterpreter->GetCurrentMacroName());
00005    dir.ReplaceAll("hbars.C","../tree/cernbuild.C");
00006    dir.ReplaceAll("/./","/");
00007    if (!gInterpreter->IsLoaded(dir.Data())) gInterpreter->LoadMacro(dir.Data());
00008    TFile *f = (TFile*)gROOT->ProcessLineFast("cernbuild(1)");
00009    if (!f) return;
00010    TTree *T = (TTree*)f->Get("T");
00011    T->SetFillColor(45);
00012    TCanvas *c1 = new TCanvas("c1","histograms with bars",700,800);
00013    c1->SetFillColor(42);
00014    c1->Divide(1,2);
00015    
00016    //horizontal bar chart
00017    c1->cd(1); gPad->SetGrid(); gPad->SetLogx(); gPad->SetFrameFillColor(33);
00018    T->Draw("Nation","","hbar2");
00019    
00020    //vertical bar chart
00021    c1->cd(2); gPad->SetGrid(); gPad->SetFrameFillColor(33);
00022    T->Draw("Division>>hDiv","","goff");
00023    TH1F *hDiv   = (TH1F*)gDirectory->Get("hDiv");
00024    hDiv->SetStats(0);
00025    TH1F *hDivFR = (TH1F*)hDiv->Clone("hDivFR");
00026    T->Draw("Division>>hDivFR","Nation==\"FR\"","goff");
00027    hDiv->SetBarWidth(0.45);
00028    hDiv->SetBarOffset(0.1);
00029    hDiv->SetFillColor(49);
00030    TH1 *h1 = hDiv->DrawCopy("bar2");
00031    hDivFR->SetBarWidth(0.4);
00032    hDivFR->SetBarOffset(0.55);
00033    hDivFR->SetFillColor(50);
00034    TH1 *h2 = hDivFR->DrawCopy("bar2,same");
00035   
00036    TLegend *legend = new TLegend(0.55,0.65,0.76,0.82);
00037    legend->AddEntry(h1,"All nations","f");
00038    legend->AddEntry(h2,"French only","f");
00039    legend->Draw();
00040    
00041    c1->cd();
00042    delete f;
00043    return c1;
00044 }