UtilAlgos/interface/MatchLessByDEta.h

0001 #ifndef MatchLessByDEta_h_
0002 #define MatchLessByDEta_h_
0003
0004 /** Provides the less operator for two pairs of matched objects based
0005  *  on deltaEta. */
0006
0007 #include "FWCore/ParameterSet/interface/ParameterSet.h"
0008
0009 namespace reco {
0010   template <typename C1, typename C2>
0011   struct MatchLessByDEta {
0012   public:
0013     MatchLessByDEta(const edm::ParameterSet& cfg, const C1& c1, const C2& c2) : c1_(c1), c2_(c2) {}
0014     bool operator()(const std::pair<size_t, size_t>& p1, const std::pair<size_t, size_t>& p2) const {
0015       typedef typename C1::value_type T1;
0016       typedef typename C2::value_type T2;
0017       const T1& p1_1 = c1_[p1.first];
0018       const T2& p1_2 = c2_[p1.second];
0019       const T1& p2_1 = c1_[p2.first];
0020       const T2& p2_2 = c2_[p2.second];
0021       if (fabs(p1_1.eta() - p1_2.eta()) < fabs(p2_1.eta() - p2_2.eta()))
0022         return true;
0023       return false;
0024     }
0025
0026   private:
0027     const C1& c1_;
0028     const C2& c2_;
0029   };
0030 }  // namespace reco
0031
0032 #endif