Class to provide resolution factors for PAT candidates. More...

#include <PhysicsTools/PatAlgos/interface/StringResolutionProvider.h>

Inheritance diagram for StringResolutionProvider:

Public Types
typedef StringObjectFunction < reco::Candidate >	Function
	short cut within the common namespace
Public Member Functions
virtual pat::CandKinResolution	getResolution (const reco::Candidate &cand) const
	get a CandKinResolution object from the service
	StringResolutionProvider (const edm::ParameterSet &cfg)
	default constructor
virtual	~StringResolutionProvider ()
	default destructor
Private Attributes
std::vector< std::string >	bins_
	a vector of strings for the binning
std::vector < pat::CandKinResolution::Scalar >	constraints_
std::vector< std::string >	funcEt_
	vectors for the resolution functions
std::vector< std::string >	funcEta_
std::vector< std::string >	funcPhi_
pat::CandKinResolution::Parametrization	parametrization_

Detailed Description

Class to provide resolution factors for PAT candidates.

A class to provide resolution functions for PAT candidates. The class is derived from the KinematicResolutionProvider class. It expects the following parameters:

parametrization : indicates the used representation (e.g. EtEtaPhi). This parameter is MANDATORY. resolutions : a vector of edm::ParameterSets, that contain the resolutions func- tionspotentially in multiple bins of a cetain parameter. For the default implementeation we have bins of reco::Candidate's eta in mind, though might be any kind of variable that is accessible as memeber function of reco::Candidate. This parameter is MANDATORY.

The edm::ParameterSets of the _resolutions_ parameter are expected to be of form:

bin : Indicated the binning compatible with the StringCutObjectSelector. If omitted no binning is applied and the obtained resolution func- tions are assumed to be valid for all candidates. This parameter is OPTIONAL. et/eta/phi : Contain the parametrization in et if working in the EtEtaPhi pa- rametrization. These parameters are OPTIONAL. They are expected to be present in the et/eta/phi representation though. constraint : adding further information on constraints. It needs to investigated further what the meaning of this parameter exactly is before we can decide about its future. This parameter is OPTIONAL.

We expect that cfi files of this form will be generated automatically. edm::ParameterSets for other represenations will be implemented on request.

Definition at line 43 of file StringResolutionProvider.h.

Member Typedef Documentation

typedef StringObjectFunction<reco::Candidate> StringResolutionProvider::Function

short cut within the common namespace

Definition at line 47 of file StringResolutionProvider.h.

Constructor & Destructor Documentation

StringResolutionProvider::StringResolutionProvider ( const edm::ParameterSet & cfg )

default constructor

Definition at line 8 of file StringResolutionProvider.cc.

References bins_, constraints_, Exception, pat::helper::ParametrizationHelper::fromString(), funcEt_, funcEta_, funcPhi_, edm::ParameterSet::getParameter(), and parametrization_.

                                                                            : constraints_() 
{ 
  typedef pat::CandKinResolution::Parametrization Parametrization;
  
  // 
  std::vector<double> constr = cfg.getParameter<std::vector<double> > ("constraints");
  constraints_.insert(constraints_.end(), constr.begin(), constr.end());
  
  std::string parametrization(cfg.getParameter<std::string> ("parametrization") );
  parametrization_ = pat::helper::ParametrizationHelper::fromString(parametrization);
  
  std::vector<edm::ParameterSet> functionSets_ = cfg.getParameter <std::vector<edm::ParameterSet> >("functions");
  for(std::vector<edm::ParameterSet>::const_iterator iSet = functionSets_.begin(); iSet != functionSets_.end(); ++iSet){
    if(iSet->exists("bin"))bins_.push_back(iSet->getParameter<std::string>("bin"));
    else if(functionSets_.size()==1)bins_.push_back("");
    else throw cms::Exception("WrongConfig") << "Parameter 'bin' is needed if more than one PSet is specified\n";

    funcEt_.push_back(iSet->getParameter<std::string>("et"));
    funcEta_.push_back(iSet->getParameter<std::string>("eta"));
    funcPhi_.push_back(iSet->getParameter<std::string>("phi"));
  }
}

StringResolutionProvider::~StringResolutionProvider ( ) [virtual]

default destructor

Definition at line 31 of file StringResolutionProvider.cc.

{
}

Member Function Documentation

pat::CandKinResolution StringResolutionProvider::getResolution ( const reco::Candidate & cand ) const [virtual]

get a CandKinResolution object from the service

Implements KinematicResolutionProvider.

Definition at line 36 of file StringResolutionProvider.cc.

References bins_, constraints_, funcEt_, funcEta_, funcPhi_, i, and parametrization_.

{ 
  int selectedBin=-1;
  for(unsigned int i=0; i<bins_.size(); ++i){
    StringCutObjectSelector<reco::Candidate> select_(bins_[i]);
    if(select_(cand)){
      selectedBin = i;
      break;
    }
  }
  std::vector<pat::CandKinResolution::Scalar> covariances(3);
  if(selectedBin>=0){
    covariances[0] = ROOT::Math::Square(Function(funcEt_ [selectedBin]).operator()(cand));
    covariances[1] = ROOT::Math::Square(Function(funcEta_[selectedBin]).operator()(cand));
    covariances[2] = ROOT::Math::Square(Function(funcPhi_[selectedBin]).operator()(cand));
  }
  // fill 0. for not selected candidates
  else for(int i=0; i<3; ++i){covariances[i] = 0.;}
  
  return pat::CandKinResolution(parametrization_, covariances, constraints_);
}