Examples/Scripts/compareHistograms.C

0001 // This file is part of the ACTS project.
0002 //
0003 // Copyright (C) 2016 CERN for the benefit of the ACTS project
0004 //
0005 // This Source Code Form is subject to the terms of the Mozilla Public
0006 // License, v. 2.0. If a copy of the MPL was not distributed with this
0007 // file, You can obtain one at https://mozilla.org/MPL/2.0/.
0008
0009 #include "TFile.h"
0010 #include "TH1F.h"
0011 #include "TROOT.h"
0012 #include "TTree.h"
0013
0014 // This root script draws the histograms with the name "hist1Name" and the name
0015 // "hist2Name" (and possibly also a third histogram with name "hist3Name") from
0016 // the input file into the same canvas with the colors given
0017
0018 void
0019 compareHistograms(std::string inFile1,
0020                   std::string hist1Name,
0021                   int         col1,
0022                   std::string inFile2,
0023                   std::string hist2Name,
0024                   int         col2,
0025                   std::string inFile3   = "",
0026                   std::string hist3Name = "",
0027                   int         col3      = 0)
0028 {
0029   std::cout << "Opening file: " << inFile1 << std::endl;
0030   TFile inputFile1(inFile1.c_str());
0031   std::cout << "Opening file: " << inFile2 << std::endl;
0032   TFile inputFile2(inFile2.c_str());
0033   std::cout << "Comparing Histograms: " << hist1Name << " & " << hist2Name
0034             << std::endl;
0035
0036   TH1F* h1 = (TH1F*)inputFile1.Get(hist1Name.c_str());
0037   TH1F* h2 = (TH1F*)inputFile2.Get(hist2Name.c_str());
0038   std::cout << "col1: " << col1 << ", col2: " << col2 << std::endl;
0039
0040   h1->SetMarkerColor(col1);
0041   h1->SetLineColor(col1);
0042   h1->SetMarkerStyle(3);
0043   h1->Draw("");
0044   h2->SetMarkerColor(col2);
0045   h2->SetLineColor(col2);
0046   h2->Draw("same");
0047   TLegend* leg = new TLegend(0.72, 0.696, 0.99, 0.936);
0048   leg->AddEntry(h1, hist1Name.c_str());
0049   leg->AddEntry(h2, hist2Name.c_str());
0050
0051   if (!inFile3.empty()) {
0052     TFile inputFile3(inFile3.c_str());
0053     TH1F* h3 = (TH1F*)inputFile3.Get(hist3Name.c_str());
0054     std::cout << " & " << hist3Name << std::endl;
0055     std::cout << "from file: " << inFile3 << std::endl;
0056     h3->SetMarkerColor(col3);
0057     h3->SetLineColor(col3);
0058     h3->Draw("same");
0059     h3->SetDirectory(0);
0060     leg->AddEntry(h3, hist3Name.c_str());
0061     inputFile3.Close();
0062   }
0063
0064   leg->Draw();
0065
0066   h1->SetDirectory(0);
0067   h2->SetDirectory(0);
0068
0069   inputFile1.Close();
0070   inputFile2.Close();
0071 }