FastJet 3.0.2
SISConePlugin.cc
00001 
00002 // fastjet stuff
00003 #include "fastjet/ClusterSequence.hh"
00004 #include "fastjet/SISConePlugin.hh"
00005 
00006 // sisocne stuff
00007 #include "siscone/momentum.h"
00008 #include "siscone/siscone.h"
00009 
00010 // other stuff
00011 #include<sstream>
00012 
00013 FASTJET_BEGIN_NAMESPACE      // defined in fastjet/internal/base.hh
00014 
00015 using namespace std;
00016 using namespace siscone;
00017 
00018 /// shortcut for converting siscone Cmomentum into PseudoJet
00019 template<> PseudoJet::PseudoJet(const siscone::Cmomentum & four_vector) {
00020   (*this) = PseudoJet(four_vector.px,four_vector.py,four_vector.pz,
00021                       four_vector.E);
00022 }
00023 
00024 
00025 /////////////////////////////////////////////
00026 // static members declaration              //
00027 /////////////////////////////////////////////
00028 std::auto_ptr<SISConePlugin>           SISConePlugin::stored_plugin;
00029 std::auto_ptr<std::vector<PseudoJet> > SISConePlugin::stored_particles;
00030 std::auto_ptr<Csiscone>                SISConePlugin::stored_siscone;
00031 
00032 
00033 /////////////////////////////////////////////
00034 // now comes the implementation itself     //
00035 /////////////////////////////////////////////
00036 string SISConePlugin::description () const {
00037   ostringstream desc;
00038   
00039   const string on = "on";
00040   const string off = "off";
00041 
00042   string sm_scale_string = "split-merge uses " + 
00043     split_merge_scale_name(Esplit_merge_scale(split_merge_scale()));
00044 
00045   desc << "SISCone jet algorithm with " ;
00046   desc << "cone_radius = "       << cone_radius        () << ", ";
00047   desc << "overlap_threshold = " << overlap_threshold  () << ", ";
00048   desc << "n_pass_max = "        << n_pass_max         () << ", ";
00049   desc << "protojet_ptmin = "    << protojet_ptmin()      << ", ";
00050   desc <<  sm_scale_string                                << ", ";
00051   desc << "caching turned "      << (caching() ? on : off);
00052   desc << ", SM stop scale = "     << _split_merge_stopping_scale;
00053 
00054   // add a note to the description if we use the pt-weighted splitting
00055   if (_use_pt_weighted_splitting){
00056     desc << ", using pt-weighted splitting";
00057   }
00058 
00059   if (_use_jet_def_recombiner){
00060     desc << ", using jet-definition's own recombiner";
00061   }
00062 
00063   // create a fake siscone object so that we can find out more about it
00064   Csiscone siscone;
00065   if (siscone.merge_identical_protocones) {
00066     desc << ", and (IR unsafe) merge_indentical_protocones=true" ;
00067   }
00068 
00069   desc << ", SISCone code v" << siscone_version();
00070 
00071   return desc.str();
00072 }
00073 
00074 
00075 // overloading the base class implementation
00076 void SISConePlugin::run_clustering(ClusterSequence & clust_seq) const {
00077 
00078   Csiscone::set_banner_stream(clust_seq.fastjet_banner_stream());
00079 
00080   Csiscone   local_siscone;
00081   Csiscone * siscone;
00082   
00083   unsigned n = clust_seq.jets().size();
00084 
00085   bool new_siscone = true; // by default we'll be running it
00086 
00087   if (caching()) {
00088 
00089     // Establish if we have a cached run with the same R, npass and
00090     // particles. If not then do any tidying up / reallocation that's
00091     // necessary for the next round of caching, otherwise just set
00092     // relevant pointers so that we can reuse and old run.
00093     if (stored_siscone.get() != 0) {
00094       new_siscone = !(stored_plugin->cone_radius()   == cone_radius()
00095                       && stored_plugin->n_pass_max() == n_pass_max()  
00096                       && stored_particles->size()    == n);
00097       if (!new_siscone) {
00098         for(unsigned i = 0; i < n; i++) {
00099           // only check momentum because indices will be correctly dealt
00100           // with anyway when extracting the clustering order.
00101           new_siscone |= !have_same_momentum(clust_seq.jets()[i], 
00102                                              (*stored_particles)[i]);
00103         }
00104       }
00105     } 
00106       
00107     // allocate the new siscone, etc., if need be
00108     if (new_siscone) {
00109       stored_siscone  .reset( new Csiscone );
00110       stored_particles.reset( new std::vector<PseudoJet>(clust_seq.jets()));
00111       reset_stored_plugin();
00112     }
00113 
00114     siscone = stored_siscone.get();
00115   } else {
00116     siscone = &local_siscone;
00117   }
00118 
00119   // make sure stopping scale is set in siscone
00120   siscone->SM_var2_hardest_cut_off = _split_merge_stopping_scale*_split_merge_stopping_scale;
00121 
00122   // set the specific parameters
00123   // when running with ghosts for passive areas, do not put the
00124   // ghosts into the stable-cone search (not relevant)
00125   siscone->stable_cone_soft_pt2_cutoff = ghost_separation_scale()
00126                                          * ghost_separation_scale();
00127   // set the type of splitting we want (default=std one, true->pt-weighted split)
00128   siscone->set_pt_weighted_splitting(_use_pt_weighted_splitting);
00129 
00130   if (new_siscone) {
00131     // transfer fastjet initial particles into the siscone type
00132     std::vector<Cmomentum> siscone_momenta(n);
00133     for(unsigned i = 0; i < n; i++) {
00134       const PseudoJet & p = clust_seq.jets()[i]; // shorthand
00135       siscone_momenta[i] = Cmomentum(p.px(), p.py(), p.pz(), p.E());
00136     }
00137     
00138     // run the jet finding
00139     //cout << "plg sms: " << split_merge_scale() << endl;
00140     siscone->compute_jets(siscone_momenta, cone_radius(), overlap_threshold(),
00141                           n_pass_max(), protojet_or_ghost_ptmin(), 
00142                           Esplit_merge_scale(split_merge_scale()));
00143   } else {
00144     // rerun the jet finding
00145     // just run the overlap part of the jets.
00146     //cout << "plg rcmp sms: " << split_merge_scale() << endl;
00147     siscone->recompute_jets(overlap_threshold(), protojet_or_ghost_ptmin(), 
00148                             Esplit_merge_scale(split_merge_scale()));
00149   }
00150 
00151   // extract the jets [in reverse order -- to get nice ordering in pt at end]
00152   int njet = siscone->jets.size();
00153 
00154   // allocate space for the extras object
00155   SISConeExtras * extras = new SISConeExtras(n);
00156 
00157   for (int ijet = njet-1; ijet >= 0; ijet--) {
00158     const Cjet & jet = siscone->jets[ijet]; // shorthand
00159     
00160     // Successively merge the particles that make up the cone jet
00161     // until we have all particles in it.  Start off with the zeroth
00162     // particle.
00163     int jet_k = jet.contents[0];
00164     for (unsigned ipart = 1; ipart < jet.contents.size(); ipart++) {
00165       // take the last result of the merge
00166       int jet_i = jet_k;
00167       // and the next element of the jet
00168       int jet_j = jet.contents[ipart];
00169       // and merge them (with a fake dij)
00170       double dij = 0.0;
00171 
00172       if (_use_jet_def_recombiner) {
00173         clust_seq.plugin_record_ij_recombination(jet_i, jet_j, dij, jet_k);
00174       } else {
00175         // create the new jet by hand so that we can adjust its user index
00176         PseudoJet newjet = clust_seq.jets()[jet_i] + clust_seq.jets()[jet_j];
00177         // set the user index to be the pass in which the jet was discovered
00178        // *** The following line was commented for 3.0.1 ***
00179         //newjet.set_user_index(jet.pass);
00180         clust_seq.plugin_record_ij_recombination(jet_i, jet_j, dij, newjet, jet_k);
00181       }
00182 
00183     }
00184 
00185     // we have merged all the jet's particles into a single object, so now
00186     // "declare" it to be a beam (inclusive) jet.
00187     // [NB: put a sensible looking d_iB just to be nice...]
00188     double d_iB = clust_seq.jets()[jet_k].perp2();
00189     clust_seq.plugin_record_iB_recombination(jet_k, d_iB);
00190 
00191     // now record the pass of the jet in the extras object
00192     extras->_pass[clust_seq.jets()[jet_k].cluster_hist_index()] = jet.pass;
00193   }
00194 
00195   // now copy the list of protocones into an "extras" objects
00196   for (unsigned ipass = 0; ipass < siscone->protocones_list.size(); ipass++) {
00197     for (unsigned ipc = 0; ipc < siscone->protocones_list[ipass].size(); ipc++) {
00198       PseudoJet protocone(siscone->protocones_list[ipass][ipc]);
00199       protocone.set_user_index(ipass);
00200       extras->_protocones.push_back(protocone);
00201     }
00202   }
00203   extras->_most_ambiguous_split = siscone->most_ambiguous_split;
00204 
00205   // tell it what the jet definition was
00206   extras->_jet_def_plugin = this;
00207 
00208   // give the extras object to the cluster sequence.
00209   clust_seq.plugin_associate_extras(std::auto_ptr<ClusterSequence::Extras>(extras));
00210 }
00211 
00212 
00213 void SISConePlugin::reset_stored_plugin() const{
00214   stored_plugin.reset( new SISConePlugin(*this));
00215 }
00216 
00217 FASTJET_END_NAMESPACE      // defined in fastjet/internal/base.hh
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends