SmearedMET.hh

// -*- C++ -*-
#ifndef RIVET_SmearedMET_HH
#define RIVET_SmearedMET_HH
 
#include "Rivet/Projection.hh"
#include "Rivet/Projections/METFinder.hh"
#include "Rivet/Projections/MissingMomentum.hh"
#include "Rivet/Tools/SmearingFunctions.hh"
#include <functional>
 
namespace Rivet {
 
 
  class SmearedMET : public METFinder {
  public:
 
 
    template<typename SMEARPARAMSFN, typename std::enable_if_t<is_same_v<invoke_result_t<SMEARPARAMSFN, Vector3, double>, METSmearParams>, int> = 0>
    SmearedMET(const MissingMomentum& mm, const SMEARPARAMSFN& metSmearParamsFn)
      : _metSmearParamsFn(metSmearParamsFn), _metSmearFn(nullptr)
        // _metSmearFn([&](const Vector3& met, double set) -> Vector3 {
        //   const METSmearParams msps = metSmearParamsFn(met, set);
        //   return MET_SMEAR_NORM(msps);
        // })
    {
      setName("SmearedMET");
      declare(mm, "TruthMET");
    }
 
    template<typename SMEARPARAMSFN, typename std::enable_if_t<is_same_v<invoke_result_t<SMEARPARAMSFN, Vector3, double>, METSmearParams>, int> = 0>
    SmearedMET(const SMEARPARAMSFN& metSmearParamsFn, const Cut& cut=Cuts::OPEN)
      : SmearedMET(MissingMomentum(cut), metSmearParamsFn)
    {  }
 
    template<typename SMEARFN, typename std::enable_if_t<is_same_v<invoke_result_t<SMEARFN, Vector3, double>, Vector3>, int> = 0>
    SmearedMET(const MissingMomentum& mm, const SMEARFN& metSmearFn)
       : _metSmearParamsFn(nullptr), _metSmearFn(metSmearFn)
    {
      setName("SmearedMET");
      declare(mm, "TruthMET");
    }
 
    template<typename SMEARFN, typename std::enable_if_t<is_same_v<invoke_result_t<SMEARFN, Vector3, double>, Vector3>, int> = 0>
    SmearedMET(const SMEARFN& metSmearFn, const Cut& cut=Cuts::OPEN)
     : SmearedMET(MissingMomentum(cut), metSmearFn)
    {  }
 
    template <typename SMEARPARAMSFN, typename SMEARFN,
              typename std::enable_if_t<is_same_v<invoke_result_t<SMEARFN, Vector3, double>, Vector3> &&
                                        is_same_v<invoke_result_t<SMEARPARAMSFN, Vector3, double>, METSmearParams>, int> = 0>
    SmearedMET(const MissingMomentum& mm, const SMEARPARAMSFN& metSmearParamsFn, const SMEARFN& metSmearFn)
      : _metSmearParamsFn(metSmearParamsFn), _metSmearFn(metSmearFn)
    {
      setName("SmearedMET");
      declare(mm, "TruthMET");
    }
 
    template <typename SMEARPARAMSFN, typename SMEARFN,
              typename std::enable_if_t<is_same_v<invoke_result_t<SMEARFN, Vector3, double>, Vector3> &&
                                        is_same_v<invoke_result_t<SMEARPARAMSFN, Vector3, double>, METSmearParams>, int> = 0>
    SmearedMET(const SMEARPARAMSFN& metSmearParamsFn, const SMEARFN& metSmearFn, const Cut& cut=Cuts::OPEN)
      : SmearedMET(MissingMomentum(cut), metSmearParamsFn, metSmearFn)
    {  }
 
 
    RIVET_DEFAULT_PROJ_CLONE(SmearedMET);
 
 
    using Projection::operator =;
 
 
    CmpState compare(const Projection& p) const {
      // const SmearedMET& other = dynamic_cast<const SmearedMET&>(p);
      // if (get_address(_metSmearParamsFn) == 0) return cmp((size_t)this, (size_t)&p);
      // if (get_address(_metSmearFn) == 0) return cmp((size_t)this, (size_t)&p);
      // MSG_TRACE("Smear hashes (params) = " << get_address(_metSmearParamsFn) << "," << get_address(other._metSmearParamsFn));
      // MSG_TRACE("Smear hashes (smear) = " << get_address(_metSmearFn) << "," << get_address(other._metSmearFn));
      // return mkPCmp(other, "TruthMET") ||
      //   cmp(get_address(_metSmearParamsFn), get_address(other._metSmearParamsFn));
      //   cmp(get_address(_metSmearFn), get_address(other._metSmearFn));
      return CmpState::UNDEF;
    }
 
 
    void project(const Event& e) {
      const METFinder& mm = apply<MissingMomentum>(e, "TruthMET");
      _set = mm.scalarEt();
      _vet = mm.vectorEt();
      if (_metSmearFn) {
        _vet = _metSmearFn(_vet, mm.scalarEt()); //< custom smearing
      } else if (_metSmearParamsFn) {
        const METSmearParams msps = _metSmearParamsFn(_vet, mm.scalarEt()); //< custom smear params
        _vet = MET_SMEAR_NORM(msps); //< normal-distribution smearing from custom params
      } else {
        throw SmearError("Attempt to smear MET with neither smearing function nor smearing-params function set");
      }
    }
 
 
 
    const Vector3& vectorPt() const { return vectorEt(); }
    double scalarPt() const { return scalarEt(); }
 
 
 
 
    const Vector3& vectorEt() const { return _vet; }
 
    double scalarEt() const { return _set; }
 
    double missingEtResolution() const {
      if (!_metSmearParamsFn)
        throw UserError("Trying to compute MET significance without a registered significance function");
      METSmearParams msps = _metSmearParamsFn(vectorEt(), scalarEt());
      //return max(msps.eResolution, msps.pResolution);
      return msps.pResolution;
    }
 
    double missingEtSignf() const {
      return missingEt() / missingEtResolution();
    }
 
 
 
    void reset() {  }
 
 
  protected:
 
    Vector3 _vet;
    double _set;
 
    METSmearParamsFn _metSmearParamsFn;
 
    METSmearFn _metSmearFn;
 
  };
 
 
}
 
#endif