#ifndef __FASTJET_TOOLS_RECLUSTER_HH__ #define __FASTJET_TOOLS_RECLUSTER_HH__ // $Id: Recluster.hh 3632 2014-08-15 10:42:53Z salam $ // // Copyright (c) 2014, Matteo Cacciari, Gavin P. Salam and Gregory Soyez // //---------------------------------------------------------------------- // This file is part of FastJet // // It is free software; you can redistribute it and/or modify it under // the terms of the GNU General Public License as published by the // Free Software Foundation; either version 2 of the License, or (at // your option) any later version. // // It is distributed in the hope that it will be useful, but WITHOUT // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY // or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public // License for more details. // // You should have received a copy of the GNU General Public License // along with this code. If not, see . //---------------------------------------------------------------------- #include #include // to derive Recluster from FOfPJ #include #include // TODO: // // - maintain Voronoi areas? Requires CSAB:has_voronoi_area() {->UNASSIGNED} // - make sure the description of the class is OK FASTJET_BEGIN_NAMESPACE // defined in fastjet/internal/base.hh //---------------------------------------------------------------------- /// \class Recluster /// Recluster a jet's constituents with a new jet definition. /// /// When Recluster is constructed from a JetDefinition, it is that /// definition that will be used to obtain the new jets. The user may /// then decide if the recombiner should be the one from that jet /// definition or if it should be acquired from the jet being /// processed (the default). /// /// Alternatively, Recluster can be constructed from a jet algorithm /// and an optional radius. In that case the recombiner is /// systematically obtained fromn the jet being processed (unless you /// call set_acquire_recombiner(false)). If only the jet algorithm is /// specified, a default radius of max_allowable_R will be assumed if /// needed. /// /// Recluster has two possible behaviours: /// /// - if it is constructed with keep=keep_only_hardest the hardest /// inclusive jet is returned as a "standard" jet with an /// associated cluster sequence (unless there were no inclusive /// jets, in which case a zero jet is returned, with no associated /// cluster sequence) /// /// - if it is constructed with keep=keep_all /// all the inclusive jets are joined into a composite jet /// /// [Note that since the structure of the resulting PseudoJet depends /// on its usage, this class inherits from /// FunctionOfPseudoJet (including a description) rather /// than being a full-fledged Transformer] /// class Recluster : public FunctionOfPseudoJet { public: /// the various options for the output of Recluster enum Keep{ /// keep only the hardest inclusive jet and return a "standard" jet with /// an associated ClusterSequence [this will be the default] keep_only_hardest, /// keep all the inclusive jets. result() will join them into a composite /// jet keep_all }; /// default constructor (uses an undefined JetDefinition, and so cannot /// be used directly). Recluster() : _new_jet_def(), _acquire_recombiner(true), _keep(keep_only_hardest), _cambridge_optimisation_enabled(true){} /// Constructs a Recluster object that reclusters a jet into a new jet /// using a generic JetDefinition /// /// \param new_jet_def the jet definition applied to do the reclustering /// \param acquire_recombiner /// when true, the reclustering will guess the /// recombiner from the input jet instead of /// the one in new_jet_def. An error is then /// thrown if no consistent recombiner is found /// \param keep_in Recluster::keep_only_hardest: the result is /// the hardest inclusive jet after reclustering, /// returned as a "standard" jet. /// Recluster::keep_all: the result is a /// composite jet with the inclusive jets as pieces. Recluster(const JetDefinition & new_jet_def, bool acquire_recombiner_in = false, Keep keep_in = keep_only_hardest) : _new_jet_def(new_jet_def), _acquire_recombiner(acquire_recombiner_in), _keep(keep_in), _cambridge_optimisation_enabled(true) {} /// Constructs a Recluster object that reclusters a jet into a new jet /// using a JetAlgorithm and its parameters /// /// \param new_jet_alg the jet algorithm applied to obtain the new clustering /// \param new_jet_radius the jet radius /// \param keep_in Recluster::keep_only_hardest: the result is /// the hardest inclusive jet after reclustering, /// returned as a "standard" jet. /// Recluster::keep_all: the result is a /// composite jet with the inclusive jets as pieces. /// /// This ctor will always acquire the recombiner from the jet being /// reclustered (it will throw if none can be found). If you wish /// to use Recluster with an algorithm that requires an extra /// parameter (like the genkt algorithm), please specify the jet /// definition fully using the constructor above. Recluster(JetAlgorithm snew_jet_alg, double new_jet_radius, Keep keep_in = keep_only_hardest); /// constructor with just a jet algorithm, but no jet radius. If the /// algorithm requires a jet radius, JetDefinition::max_allowable_R will be used. /// Recluster(JetAlgorithm new_jet_alg, Keep keep_in = keep_only_hardest); /// default dtor virtual ~Recluster(){} //---------------------------------------------------------------------- // tweaking the behaviour and corresponding enquiry functions /// set whether the reclustering should attempt to acquire a /// recombiner from the input jet void set_acquire_recombiner(bool acquire) {_acquire_recombiner = acquire;} /// returns true if this reclusterer is set to acquire the /// recombiner from the input jet bool acquire_recombiner() const{ return _acquire_recombiner;} /// sets whether to try to optimise reclustering with /// Cambridge/Aachen algorithms (by not reclustering if the /// requested C/A reclustering can be obtained by using subjets of /// an input C/A jet or one composed of multiple C/A pieces from the /// same clustering sequence). By default this is enabled, and /// _should_ always be correct; disable it to test this statement! void set_cambridge_optimisation(bool enabled){ _cambridge_optimisation_enabled = enabled;} /// sets whether to try to optimise reclustering with Cambridge/Aachen algorithms (US spelling!) void set_cambridge_optimization(bool enabled){ _cambridge_optimisation_enabled = enabled;} /// returns true if the reclusterer tries to optimise reclustering /// with Cambridge/Aachen algorithms bool cambridge_optimization(){return _cambridge_optimisation_enabled;} bool cambridge_optimisation(){return _cambridge_optimisation_enabled;} /// set the behaviour with regards to keeping all resulting jets or /// just the hardest. void set_keep(Keep keep_in) {_keep = keep_in;} /// returns the current "keep" mode i.e. whether only the hardest /// inclusive jet is returned or all of them (see the Keep enum above) Keep keep() const{ return _keep;} //---------------------------------------------------------------------- // retrieving info about the behaviour /// class description virtual std::string description() const; //---------------------------------------------------------------------- // core action of ths class /// runs the reclustering and sets kept and rejected to be the jets /// of interest (with non-zero rho, they will have been /// subtracted). Normally this will be accessed through the base /// class's operator(). /// /// \param jet the jet that gets reclustered /// \return the reclustered jet virtual PseudoJet result(const PseudoJet & jet) const; /// A lower-level method that does the actual work of reclustering /// the input jet. The resulting jets are stored in output_jets. /// The jet definition that has been used can be accessed from the /// output_jets' ClusterSequence. /// /// \param input_jet the (input) jet that one wants to recluster /// \param output_jets inclusive jets resulting from the new clustering /// /// Returns true if the C/A optimisation has been used (this means /// that generate_output_jet then has to watch out for non-explicit-ghost /// areas that might be leftover) bool get_new_jets_and_def(const PseudoJet & input_jet, std::vector & output_jets) const; /// given a set of inclusive jets and a jet definition used, create the /// resulting PseudoJet; /// /// If ca_optimisation_used then special care will be taken in /// deciding whether the final jet can legitimately have an area. PseudoJet generate_output_jet(std::vector & incljets, bool ca_optimisation_used) const; private: /// set the reclustered elements in the simple case of C/A+C/A void _recluster_ca(const std::vector & all_pieces, std::vector & incljets, double Rfilt) const; /// set the reclustered elements in the generic re-clustering case void _recluster_generic(const PseudoJet & jet, std::vector & incljets, const JetDefinition & new_jet_def, bool do_areas) const; // a series of checks //-------------------------------------------------------------------- /// get the pieces down to the fundamental pieces bool _get_all_pieces(const PseudoJet &jet, std::vector &all_pieces) const; /// associate the proper recombiner taken from the underlying pieces /// (an error is thrown if the pieces do no share a common /// recombiner) void _acquire_recombiner_from_pieces(const std::vector &all_pieces, JetDefinition &new_jet_def) const; /// check if one can apply the simplified trick for C/A subjets bool _check_ca(const std::vector &all_pieces, const JetDefinition &new_jet_def) const; /// check if the jet (or all its pieces) have explicit ghosts /// (assuming the jet has area support /// /// Note that if the jet has an associated cluster sequence that is no /// longer valid, an error will be thrown bool _check_explicit_ghosts(const std::vector &all_pieces) const; JetDefinition _new_jet_def; ///< the jet definition to use to extract the jets bool _acquire_recombiner; ///< get the recombiner from the input ///< jet rather than from _new_jet_def Keep _keep; ///< dictates which inclusive jets are kept and ///< which are returned (see Keep above) bool _cambridge_optimisation_enabled; ///