Add file onlineGUI/Macros/comp_histos.C

comp_histos.C does a chi-squared comparision between histograms
  in two root files. Need to create the subdirectory Output
  The execution is
  .x Macros/comp_histos.C("oldfile.root","newfile.root")

  Main purpose is for comparing histograms
  after changes to hcana. Histograms which are exactly the same
  have a chi-square = 0 .
  For histograms that fail the chi-square test, a list of
  names in placed in Output/hist_diff_NoMatch_output.txt
  and the histograms are plotted and the plots saved to
   Output/hist_diff_NoMatchoutput.pdf
  For histograms that pass the chi-square test, a list of
  names in placed in Output/hist_diff_Match_output.txt

onlineGUI/.gitignore

@@ -4,3 +4,6 @@ online
 *#
 onlineDict.C
 .root_history
+*.root
+*.pdf
+

onlineGUI/Macros/comp_histos.C

+#include <iostream>
+#include "TFile.h"
+#include "TH1D.h"
+#include "TKey.h"
+
+using namespace std;
+
+void comp_histos(TString old_file="",TString new_file="") {
+  if (old_file=="") {
+    cout << "Enter original version root file name: " << endl;
+    cin >> old_file;
+  }
+  if (new_file=="") {
+    cout << "Enter new version root file name: " << endl;
+    cin >> new_file;
+  }
+  TFile* f1= new TFile(old_file,"READ");
+  if (f1->IsZombie()) {
+    cout << "Cannot find : " << old_file << endl;
+    return;
+  } 
+  TFile* f2= new TFile(new_file,"READ");
+  if (f2->IsZombie()) {
+    cout << "Cannot find : " << new_file << endl;
+    return;
+  } 
+  TIter nextkey1(f1->GetListOfKeys());
+  TIter nextkey2(f2->GetListOfKeys());
+  TKey *key1;
+  TKey *key2;
+  ofstream Matchoutfile("Output/hist_diff_Match_output.txt");
+  ofstream NoMatchoutfile("Output/hist_diff_NoMatch_output.txt");
+  Int_t cnt=0;
+  Int_t igood;
+  Double_t test_chi;
+  Int_t test_ndf;
+  TCanvas *can = new TCanvas("can"," ",800,800);
+  while ( (key1= (TKey*)nextkey1()) && (key2= (TKey*)nextkey2())) {
+    TClass *cl1= gROOT->GetClass(key1->GetClassName());
+    TClass *cl2= gROOT->GetClass(key2->GetClassName());
+    if ( cl1->InheritsFrom ("TH1") && cl2->InheritsFrom ("TH1") && !(cl1->InheritsFrom ("TH2") && cl2->InheritsFrom ("TH2"))) {
+      TH1 *h1 = (TH1*)key1->ReadObj();
+      TH1 *h2 = (TH1*)key2->ReadObj();
+      if (h1->Integral()>0 && h2->Integral()>0) {
+	h1->Chi2TestX(h2,test_chi,test_ndf,igood,"UU");
+      if (test_chi >0) {
+	NoMatchoutfile << " histogram " << key1->GetTitle() << " does not match chi2 = "  << test_chi<< " " << endl;
+      can->Clear();
+      can->Divide(1,1);
+	can->cd(1);
+       h1->Draw();
+      h2->Draw("same");
+      h2->SetLineColor(2);
+      cnt++;
+      if (cnt == 1) can->Print("Output/hist_diff_NoMatchoutput.pdf(");
+      if (cnt >1) can->Print("Output/hist_diff_NoMatchoutput.pdf");
+       can->Update();
+       can->WaitPrimitive();
+       //can->Clear();
+      } else {
+ 	Matchoutfile << " histogram " << key1->GetTitle() << " matches"  << endl;
+      }
+      }
+    }
+    //
+    if ( cl1->InheritsFrom ("TH2") && cl2->InheritsFrom ("TH2")) {
+      TH2 *hh1 = (TH2*)key1->ReadObj();
+      TH2 *hh2 = (TH2*)key2->ReadObj();
+      if ( (hh1->Integral()>0 && hh2->Integral()>0)) {
+	hh1->Chi2TestX(hh2,test_chi,test_ndf,igood,"UU");
+	if (test_chi >1) {
+	NoMatchoutfile << "2d  histogram " << key1->GetTitle() << " does not match chi2 = "  << test_chi<< " " << endl;
+      can->Clear();
+      can->Divide(1,2);
+      can->cd(1);
+       hh1->Draw("colz");
+      can->cd(2);
+       hh2->Draw("colz");
+       can->Update();
+       can->WaitPrimitive();
+      cnt++;
+      if (cnt == 1) can->Print("Output/hist_diff_NoMatchoutput.pdf(");
+      if (cnt >1) can->Print("Output/hist_diff_NoMatchoutput.pdf");
+       //can->Clear();
+      } else {
+ 	Matchoutfile << " histogram " << key1->GetTitle() << " matches" << endl;
+      }
+      }
+    }
+    //
+    //
+  }
+  //
+  if (cnt >0) can->Print("Output/hist_diff_NoMatchoutput.pdf)");
+  can->Close();
+  if (cnt == 0) NoMatchoutfile << " All histograms matched. Congratulations !" <<  endl;
+  if (cnt == 0) cout << " All histograms matched. Congratulations !" <<  endl;
+  if (cnt > 0) NoMatchoutfile << " Some histograms did not matched. " <<  endl;
+  if (cnt > 0) cout << " Some histograms did not matched. " <<  endl;
+  cout << " Histograms with matched output are listed in Output/hist_diff_Match_output.txt" << endl;
+  cout << " Histograms with unmatched output are listed in Output/hist_diff_NoMatch_output.txt"<< endl;
+  //
+}