/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.31/xAODEgamma/xAODEgamma/EgammaTruthxAODHelpers.h

// Dear emacs, this is -*- c++ -*-
// $Id: EgammaTruthxAODHelpers.h 718563 2016-01-19 19:30:02Z christos $
#ifndef XAOD_EGAMMATRUTHXAODHELPERS_H
#define XAOD_EGAMMATRUTHXAODHELPERS_H

#include "xAODEgamma/EgammaFwd.h"
#include "xAODEgamma/ElectronFwd.h"
#include "xAODEgamma/PhotonFwd.h"
#include "xAODTracking/TrackParticleFwd.h"
#include "xAODTruth/TruthParticleContainer.h"
#include "xAODTruth/TruthParticle.h"

#include <cstddef>
#include <set>

namespace xAOD {

  namespace EgammaHelpers{
    
    template<class T>
    const T* getLink(const xAOD::IParticle* particle, std::string name){
      if (!particle) return 0;
      typedef ElementLink< DataVector<T> > Link_t;
      
      if (!particle->isAvailable< Link_t >(name) ) { 
      return 0; 
    }  
      const Link_t link = particle->auxdata<Link_t>(name);
      if (!link.isValid()) { 
      return 0; 
    }
      return *link;
    }
    
    const xAOD::Electron* getRecoElectron(const xAOD::TruthParticle*);
    
    const xAOD::Photon* getRecoPhoton(const xAOD::TruthParticle* particle);
        
    bool isTrueConvertedPhoton(const xAOD::Photon* ph, float maxRadius = 800.);

    bool isTrueConvertedPhoton(const xAOD::TruthParticle* truePh, float maxRadius = 800.);

    const xAOD::TruthParticle* getBkgElectronMother(const xAOD::Electron* el,const unsigned int barcodecut=0);

    const xAOD::TruthParticle* getBkgElectronMother(const xAOD::TruthParticle* truthel, const unsigned int barcodecut=0);

    std::vector<const xAOD::TruthParticle*> 
    getBkgElectronLineage(const xAOD::Electron* el,const unsigned int barcodecut=0);
    
    std::vector<const xAOD::TruthParticle*> 
    getBkgElectronLineage(const xAOD::TruthParticle* truthel,const unsigned int barcodecut=0);

        
  }// EgammaHelpers

} // namespace xAOD
  
#endif // XAOD_EGAMMAXAODHELPERS_H

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