thailand2017/tut_ana_fast.C

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class RhoCandList;
class RhoCandidate;
class PndAnaPidSelector;
class PndAnaPidCombiner;
class PndAnalysis;

// **** some auxilliary functions in auxtut.C ****
// - FairRunAna* initrun(TString prefix, TString outfile, int min=-1, int max=-1) --> Init FairRunAna
// - plotmyhistos()               --> Plots all histograms in current TDirectory on a autosized canvas
// - writemyhistos()              --> Writes all histos in current TFile 
// - fillM(RhoCandList l, TH1* h) --> Fill mass histogram h with masses of candidates in l
// - RemoveGeoManager()           --> Temporary fix for error on macro exit   
// **** some auxilliary functions in auxtut.C ****
#include "auxtut.C"


// *** routine to only keep PID matched candidates in list
int SelectTruePid(PndAnalysis *ana, RhoCandList &l)
{
        int removed = 0;
        
        for (int ii=l.GetLength()-1;ii>=0;--ii)
        {
                if ( !(ana->McTruthMatch(l[ii])) )
                {
                        l.Remove(l[ii]);
                        removed++;
                }
        }
        
        return removed;
}


void tut_ana_fast(int nevts = 0, TString prefix = "signal")
{
        // *** some variables
        int i=0,j=0, k=0, l=0;
        gStyle->SetOptFit(1011);
        
        // *** the output file for FairRunAna
        TString OutFile="out_dummy.root";  
                                        
        // *** the files coming from the simulation
        TString inPidFile  = prefix+"_fast.root";    // this file contains the PndPidCandidates and McTruth
        
        // *** PID table with selection thresholds; can be modified by the user
        TString pidParFile = TString(gSystem->Getenv("VMCWORKDIR"))+"/macro/params/all.par";    
        
        // *** initialization
        FairRunAna* fRun = new FairRunAna();
        fRun->SetSource(new FairFileSource(inPidFile));
        fRun->SetOutputFile(OutFile);
        
        // *** take constant field; needed for PocaVtx
        RhoCalculationTools::ForceConstantBz(20.0);
        
        fRun->Init(); 
        
        // *** create an output file for all histograms
        TFile *out = TFile::Open(prefix+"_ana_fast.root","RECREATE");

        // ------------------------------
        // Now the analysis stuff comes...
        // ------------------------------

        // *** the data reader object
        PndAnalysis* theAnalysis = new PndAnalysis();
        if (nevts==0) nevts= theAnalysis->GetEntries();

        // ---------------------------------------------------------------------
        // ---------------------------------------------------------------------
        // ---------------------------------------------------------------------
        // This macro combines all tasks (combinatorics, MC truth, PID, fitting) 
        // try to complete everything, perhaps for a different decay mode
        // ---------------------------------------------------------------------
        // ---------------------------------------------------------------------
        // ---------------------------------------------------------------------

        // #### EXERCISE:  create all necessary histograms
        // ...
                
        // #### EXERCISE:  create RhoCandLists for the analysis, mass selector, etc...
        
        // ***
        // the event loop
        // ***
        while (theAnalysis->GetEvent() && i++<nevts)
        {
                // BE AWARE : The pid algos are named differently for FastSim, so simply take this one
                TString pidalgo = "PidChargedProbability";
                
                // #### EXERCISE
                // (1) combinatorics with desired PID algorithms (for FastSim use 'PidChargedProbability') and tightness, and PDG set for truth match
                // (2) select rought mass window for resonances
                // (3) do vertex fitting for resonances to charged particles
                // (4) fill final histograms, with and without truth match      
        }
        
        // *** change to directory where histograms are created
        out->cd();

        // *** plot all histos
        plotmyhistos();
        
        // *** write out all the histos to file
        int nhist = writemyhistos();
        cout<<"Writing "<<nhist<<" histograms to file"<<endl;           
        out->Save();    
        
        // *** temporaty fix to avoid error on macro exit
        //RemoveGeoManager();
}