MuonTrackPerformanceAlg::EventSummary Node1 MuonTrackPerformanceAlg ::EventSummary Node2 std::vector< MuonTrackPerformance Alg::TrackSummary > Node2->Node1 +trackSummary Node3 MuonTrackPerformanceAlg ::TrackSummary Node3->Node2 +elements Node4 std::string Node4->Node1 +eventNumber Node4->Node3 +trackPars +chambers Node6 std::vector< std::string > Node4->Node6 +elements Node5 std::basic_string< char > Node5->Node4 Node6->Node3 +missingChambers