File: ParticleMatcher.h

This file may become a part of CLHEP - a Class Library for High Energy Physics.

This is the definition of the HepParticleMatcher class.

HepParticleMatcher is an abstract base class used to represent groups of HepParticleData objects. It contains an std::set of pointers to matched HepParticleData objects and an std::set of pointers to other HepParticleMatcher objects which matches a subset of the matched HepParticleData objects.

A derived class should implement at least two methods:

• matchCheck(const HepParticleData &) should be a static method returning true if the HepParticleData object be included among the matched particles.
• checkMatch(const HepParticleData &) must return the result of the static matchCheck() method.
In addition, the constructor must call the constructor of HepParticleMatcher class giving a string to be used as identfier for the derived matcher class.

To simplified the implementation of derived classes a macro called HEP_PARTICLE_MATCHER is defined whose argument are the name of the derived class, the name used as the identifier, and an identifier used as argument for the static matchCheck() method. The use of the macro must be followed by the implementation of the matchCheck() method encosed in curly brackets using the given identifier. See example below. There is also a templated helper class called HepDerivedMatcher for the same purpose. Again see the example below.

When a object of a derived class is added to HepPDTable, it will be presented to all HepParticleData objects via the checkMatch() method and the matched particles will be added to the list in the base class.

If all the matched particles have common properties, the HepParticleMatcher objects will also have these properties accessible with the mass(), width(), cTau(), iCharge(), iSpin(), iColor() and stable() methods.

A particle matcher class matching any lepton may be implemented with the HEP_PARTICLE_MATCHER as follows

HEP_PARTICLE_MATCHER(HepLeptonMatcher,"Lepton",pd) {
 return HepBoolean( abs(pd.id()) > 10 && abs(pd.id()) < 19 );
}


This class can also be implemented with the templated HepDerivedMatcher class as follows:

struct MatchLeptons {
 static HepString name () { return "Lepton";}
 static HepBoolean check(const HepParticleData & pd) {
  return HepBoolean( abs(pd.id()) > 10 && abs(pd.id()) < 19 );
 }
};
typedef HepDerivedMatcher<MatchLeptons> HepLeptonMatcher;

PDT.h PDTable.h ParticleData.h StandardMatchers.h CombinedMatcher.h

Leif Lönnblad

typedef set<const HepParticleData *,
  less<const HepParticleData *> > ParticleSet;
typedef set<const HepParticleMatcher*,
  less<const HepParticleMatcher*> > MatcherSet;

class HepPDTable;

inline virtual ~HepParticleMatcher();
The destructor. Note that the only (default) constructor is protected.

inline const HepString & name() const;
Return the name of this matcher

virtual HepBoolean checkMatch(const HepParticleData &) const = 0;
Check if a particle meets the criteria. To be implemented by derived classes where it should call the static function matchCheck(const HepParticleData &).

inline HepBoolean matches(const HepParticleData &) const;
Check if a given particle belongs to the set of matches

inline HepBoolean matches(const HepParticleMatcher &) const;
Check if a particle matcher belongs to the set of matches.

inline const ParticleSet & particles() const;
inline const MatcherSet & matchers() const;
inline ParticleSet::const_iterator begin() const;
inline ParticleSet::const_iterator end() const;
inline ParticleSet::const_iterator
  find(const HepParticleData *) const;
Access to the map of matching particle and matchers. Also access the begin, end and find methods of the set of matching particles.

inline HepDouble mass() const;
Returns the common mass of the matching particles. If all matching particles do not have exactly the same mass -1.0 is returned.

inline HepDouble width() const;
Returns the common width of the matching particles. If all matching particles do not have exactly the same width -1.0 is returned.

inline HepDouble cTau() const;
Returns the common decay length of the matching particles. If all matching particles do not have exactly the same decay length -1.0 is returned.

inline HepPDT::HepCharge iCharge() const;
inline HepBoolean charged() const;
inline HepBoolean positive() const;
inline HepBoolean negative() const;
If all matching particles have the same charge the common charge is returned. Otherwise if all are positive (negative), HepPDT::Cpositive (HepPDT::Cnegative) is returned. Otherwise if all are charged, HepPDT::Ccharged is returned. Otherwise HepPDT::Cundefined is returned.

inline HepPDT::HepSpin iSpin() const;
If all matching particles have the same spin the common spin is returned. Otherwise HepPDT::Sundefined is returned.

inline HepPDT::HepColor iColor() const;
inline HepBoolean colored() const;
If all matching particles have the same color the common color is returned. Otherwise if all are colored, HepPDT::colcolored is returned. Otherwise HepPDT::colundefined is returned.

inline HepInt stable() const;
Returns (0)1 if all matching particles are (un)stable. Otherwise -1 is returned.

inline const HepParticleMatcher * CC() const;
HepBoolean CC(HepParticleMatcher &);
Get/set a matcher object matching the antiparticles of this. If no-one exists 0 is returned by the get function. If the argument of the set functions does not match the anti-particles of this, false is returned..

HepBoolean checkCC(const HepParticleMatcher &) const;
Check if a given matcher matches all the antiparticles of this, but do not do anything.

void init();
Used for particle matchers not handled by the HepPDTable object to initialize the list of matching particles.

void addIfMatch(const HepParticleData &);
void addIfMatch(const HepParticleMatcher &);
Add a particle or a particle matcher id to the set of matching particles if it meets the criteria.

inline HepParticleMatcher(const HepString &);
Constructor only used by derived objects.

inline void clear();
Clear information about matching particles and matchers.

HepString idString;
A character string for identification.

ParticleSet matchingParticles;
The set of particle data objects matched by this matcher.

MatcherSet matchingMatchers;
A set of matchers which matches a subset of this matcher.

HepDouble commonMass;
HepDouble commonWidth;
HepDouble commonCTau;
HepPDT::HepCharge commonCharge;
HepPDT::HepSpin commonSpin;
HepPDT::HepColor commonColor;
HepInt commonStable;
Variables containing common properties of all matched particles. All are set to a sensible 'undefined' value if the properties differs between the matched particles.

const HepParticleMatcher * antiPartner;
Pointer to a matcher object which matches all anti particles which are matched by this matcher.

This macro is depreciated. Please use the template below instead.



template <class T>

HepParticleMatcher

HepDerivedMatcher(const HepString & m = T::name())
  : HepParticleMatcher(m) {}
virtual ~HepDerivedMatcher() {}
virtual HepBoolean checkMatch(const HepParticleData & pd ) const {
  return matchCheck(pd);
}
static HepBoolean matchCheck(const HepParticleData & pd) {
  return T::check(pd);
}

DEFINED MACROS

HepParticleMatcher_H_INCLUDED
inline
HEP_PARTICLE_MATCHER(className, theName, pd)

INCLUDED FILES

CLHEP/PDT/ParticleData.h
set
CLHEP/PDT/ParticleMatcher.icc