Plot the occupancy by lcn from a rat ds root file

PlotOccupancy.cc

#include <RAT/DS/Root.hh>
#include <RAT/DS/EV.hh>
#include <RAT/DS/Run.hh>

#include <TH1D.h>
#include <TTree.h>
#include <TFile.h>

#include <time.h>
using namespace std;

void
LoadRootFile( const char* lpFile,
              TTree **tree,
              RAT::DS::Root **rDS,
              RAT::DS::Run **rRun );

void
PlotOccupancy( const char* inFile )
{
  // Load the root file first  RAT::DS::Root* rDS;
  RAT::DS::Run* rRun;
  TTree *tree;
  LoadRootFile( inFile, &tree, &rDS, &rRun );

  time_t codeStart = time( NULL );
  TH1D* occupancyPlot = new TH1D( "occupancy", "occupancy", 10000, -0.5, 9999.5 );

  for( int iEvent = 0; iEvent < tree->GetEntries(); iEvent++ )
    {
      if( iEvent % 100 == 0 )
        cout << iEvent << " finished at " << time( NULL ) - codeStart << endl;
      tree->GetEntry( iEvent );
      for( int iEV = 0; iEV < rDS->GetEVCount(); iEV++ )
        for( int iPMT = 0; iPMT < rDS->GetEV( iEV )->GetPMTCalCount(); iPMT++ )
          occupancyPlot->Fill( rDS->GetEV( iEV )->GetPMTCal( iPMT )->GetID() );
    }
occupancyPlot->Draw();
}

void
LoadRootFile( const char* lpFile,
              TTree **tree,
              RAT::DS::Root **rDS,
              RAT::DS::Run **rRun )
{
  TFile *file = new TFile( lpFile );
  (*tree) = (TTree*)file->Get( "T" );
  TTree *runTree = (TTree*)file->Get( "runT" );

  *rDS = new RAT::DS::Root();

  (*tree)->SetBranchAddress( "ds", &(*rDS) );

  *rRun = new RAT::DS::Run();

  runTree->SetBranchAddress( "run", &(*rRun) );
  runTree->GetEntry();
}