CandAlgos/plugins/ParticleDecayProducer.cc

0001 /**\class ParticleDecayProducer

0002  *

0003  * Original Author:  Nicola De Filippis

0004  *

0005  */
0006
0007 // user include files

0008 #include "FWCore/Framework/interface/Frameworkfwd.h"
0009 #include "FWCore/Framework/interface/global/EDProducer.h"
0010 #include "FWCore/ParameterSet/interface/ParameterSet.h"
0011 #include "FWCore/Utilities/interface/InputTag.h"
0012 #include "DataFormats/Candidate/interface/Candidate.h"
0013 #include <vector>
0014
0015 class ParticleDecayProducer : public edm::global::EDProducer<> {
0016 public:
0017   explicit ParticleDecayProducer(const edm::ParameterSet&);
0018   ~ParticleDecayProducer() override = default;
0019
0020 private:
0021   void produce(edm::StreamID, edm::Event& e, edm::EventSetup const& c) const override;
0022   edm::EDGetTokenT<reco::CandidateCollection> genCandidatesToken_;
0023   const int motherPdgId_;
0024   const std::vector<int> daughtersPdgId_;
0025   const std::string decayChain_;
0026   std::vector<std::string> valias;
0027 };
0028
0029 // Candidate handling

0030 #include "DataFormats/Candidate/interface/CandMatchMap.h"
0031 #include "DataFormats/Common/interface/AssociationVector.h"
0032 #include "CommonTools/Utils/interface/PtComparator.h"
0033 #include "FWCore/Framework/interface/Event.h"
0034 #include <sstream>
0035 using namespace edm;
0036 using namespace std;
0037 using namespace reco;
0038
0039 // constructors

0040 ParticleDecayProducer::ParticleDecayProducer(const edm::ParameterSet& iConfig)
0041     : genCandidatesToken_(consumes<CandidateCollection>(iConfig.getParameter<InputTag>("src"))),
0042       motherPdgId_(iConfig.getParameter<int>("motherPdgId")),
0043       daughtersPdgId_(iConfig.getParameter<vector<int> >("daughtersPdgId")),
0044       decayChain_(iConfig.getParameter<std::string>("decayChain")) {
0045   string alias;
0046   produces<CandidateCollection>(alias = decayChain_ + "Mother").setBranchAlias(alias);
0047   for (unsigned int j = 0; j < daughtersPdgId_.size(); ++j) {
0048     ostringstream index, collection;
0049     index << j;
0050     collection << decayChain_ << "Lepton" << index.str();
0051     valias.push_back(collection.str());
0052     produces<CandidateCollection>(valias.at(j)).setBranchAlias(valias.at(j));
0053   }
0054 }
0055
0056 void ParticleDecayProducer::produce(edm::StreamID, edm::Event& iEvent, edm::EventSetup const&) const {
0057   // get gen particle candidates

0058   const edm::Handle<CandidateCollection> genCandidatesCollection = iEvent.getHandle(genCandidatesToken_);
0059
0060   unique_ptr<CandidateCollection> mothercands(new CandidateCollection);
0061   unique_ptr<CandidateCollection> daughterscands(new CandidateCollection);
0062   size_t daughtersize = daughtersPdgId_.size();
0063   for (CandidateCollection::const_iterator p = genCandidatesCollection->begin(); p != genCandidatesCollection->end();
0064        ++p) {
0065     if (p->pdgId() == motherPdgId_ && p->status() == 3) {
0066       mothercands->push_back(p->clone());
0067       size_t ndau = p->numberOfDaughters();
0068       for (size_t i = 0; i < ndau; ++i) {
0069         for (size_t j = 0; j < daughtersize; ++j) {
0070           if (p->daughter(i)->pdgId() == daughtersPdgId_[j] && p->daughter(i)->status() == 3) {
0071             daughterscands->push_back(p->daughter(i)->clone());
0072           }
0073         }
0074       }
0075     }
0076   }
0077
0078   iEvent.put(std::move(mothercands), decayChain_ + "Mother");
0079   daughterscands->sort(GreaterByPt<reco::Candidate>());
0080
0081   for (unsigned int row = 0; row < daughtersize; ++row) {
0082     unique_ptr<CandidateCollection> leptonscands_(new CandidateCollection);
0083     leptonscands_->push_back((daughterscands->begin() + row)->clone());
0084     iEvent.put(std::move(leptonscands_), valias.at(row));
0085   }
0086 }
0087
0088 #include "FWCore/Framework/interface/MakerMacros.h"
0089 DEFINE_FWK_MODULE(ParticleDecayProducer);