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Calculate the Parisi event shape tensor (or linear momentum tensor). More...

#include <ParisiTensor.hh>

List of all members.

Public Member Functions

 ParisiTensor (const FinalState &fsp)
 Constructor. The provided FinalState projection must live throughout the run.
 DEFAULT_RIVET_PROJ_CLONE (ParisiTensor)
 Clone on the heap.
void clear ()
 Clear the projection.
bool before (const Projection &p) const
virtual const std::set< PdgIdPairbeamPairs () const
virtual std::string name () const
 Get the name of the projection.
ProjectionaddPdgIdPair (PdgId beam1, PdgId beam2)
 Add a colliding beam pair.
LoggetLog () const
 Get a Log object based on the getName() property of the calling projection object.
void setName (const std::string &name)
 Used by derived classes to set their name.
void markAsOwned () const
Access the C and D params.
double C () const
double D () const
Access the eigenvalues of \f$\theta\f$.
double lambda1 () const
double lambda2 () const
double lambda3 () const
Standard constructors and destructors.
virtual unique_ptr< Projectionclone () const =0
 Clone on the heap.
Projection "getting" functions
std::set< ConstProjectionPtrgetProjections () const
 Get the contained projections, including recursion.
template<typename PROJ >
const PROJ & getProjection (const std::string &name) const
const ProjectiongetProjection (const std::string &name) const
template<typename PROJ >
const PROJ & get (const std::string &name) const
Projection applying functions
template<typename PROJ >
const PROJ & applyProjection (const Event &evt, const Projection &proj) const
 Apply the supplied projection on event evt.
template<typename PROJ >
const PROJ & applyProjection (const Event &evt, const PROJ &proj) const
 Apply the supplied projection on event evt.
template<typename PROJ >
const PROJ & applyProjection (const Event &evt, const std::string &name) const
template<typename PROJ >
const PROJ & apply (const Event &evt, const Projection &proj) const
template<typename PROJ >
const PROJ & apply (const Event &evt, const PROJ &proj) const
template<typename PROJ >
const PROJ & apply (const Event &evt, const std::string &name) const

Protected Member Functions

void project (const Event &e)
 Perform the projection on the Event.
int compare (const Projection &p) const
 Compare with other projections.
Cmp< ProjectionmkNamedPCmp (const Projection &otherparent, const std::string &pname) const
Cmp< ProjectionmkPCmp (const Projection &otherparent, const std::string &pname) const
ProjectionHandlergetProjHandler () const
 Get a reference to the ProjectionHandler for this thread.
const Projection_applyProjection (const Event &evt, const std::string &name) const
const Projection_applyProjection (const Event &evt, const Projection &proj) const
Projection registration functions
template<typename PROJ >
const PROJ & declareProjection (const PROJ &proj, const std::string &name)
 Register a contained projection.
template<typename PROJ >
const PROJ & declare (const PROJ &proj, const std::string &name)
 Register a contained projection (user-facing version)
template<typename PROJ >
const PROJ & addProjection (const PROJ &proj, const std::string &name)
 Register a contained projection (user-facing version)
const Projection_declareProjection (const Projection &proj, const std::string &name)
 Untemplated function to do the work...

Protected Attributes

bool _allowProjReg
 Flag to forbid projection registration in analyses until the init phase.

Private Attributes

double _C
 The Parisi event shape variables.
double _D
double _lambda [3]
 Eigenvalues.

Friends

class Event
 Event is a friend.
class Cmp< Projection >
 The Cmp specialization for Projection is a friend.

Detailed Description

Calculate the Parisi event shape tensor (or linear momentum tensor).

The Parisi event shape C and D variables are derived from the eigenvalues of the linear momentum tensor

\[ \theta^{\alpha \beta} = \frac{\sum_i \frac{p_i^\alpha p_i^\beta}{|\mathbf{p}_i|}} {\sum_i |\mathbf{p}_i|} \]

which is actually a linearized (and hence infra-red safe) version of the Sphericity tensor.

Defining the three eigenvalues of $\theta$ $ \lambda_1 \ge \lambda_2 \ge \lambda_3 $, with $ \lambda_1 + \lambda_2 + \lambda_3 = 1 $, the C and D parameters are defined as

\[ C = 3(\lambda_1\lambda_2 + \lambda_1\lambda_3 + \lambda_2\lambda_3) \]

and

\[ D = 27 \lambda_1\lambda_2\lambda_3 \]

Internally, this Projection uses the Sphericity projection with the generalising $r$ parameter set to 1.

Definition at line 39 of file ParisiTensor.hh.


Constructor & Destructor Documentation

ParisiTensor ( const FinalState fsp) [inline]

Constructor. The provided FinalState projection must live throughout the run.

Definition at line 43 of file ParisiTensor.hh.

    {
      setName("ParisiTensor");
      addProjection(fsp, "FS");
      addProjection(Sphericity(fsp, 1.0), "Sphericity");
      clear();
    }

Member Function Documentation

const Projection & _applyProjection ( const Event evt,
const std::string &  name 
) const [protected, inherited]

Non-templated version of string-based applyProjection, to work around header dependency issue.

Definition at line 22 of file ProjectionApplier.cc.

                                                                                  {
    return evt.applyProjection(getProjection(name));
  }
const Projection & _applyProjection ( const Event evt,
const Projection proj 
) const [protected, inherited]

Non-templated version of proj-based applyProjection, to work around header dependency issue.

Definition at line 28 of file ProjectionApplier.cc.

                                                                                      {
    return evt.applyProjection(proj);
  }
const Projection & _declareProjection ( const Projection proj,
const std::string &  name 
) [protected, inherited]

Untemplated function to do the work...

Definition at line 34 of file ProjectionApplier.cc.

                                                                             {
    if (!_allowProjReg) {
      cerr << "Trying to register projection '"
           << proj.name() << "' before init phase in '" << this->name() << "'." << endl;
      exit(2);
    }
    const Projection& reg = getProjHandler().registerProjection(*this, proj, name);
    return reg;
  }
Projection& addPdgIdPair ( PdgId  beam1,
PdgId  beam2 
) [inline, inherited]

Add a colliding beam pair.

Definition at line 108 of file Projection.hh.

                                                       {
      _beamPairs.insert(PdgIdPair(beam1, beam2));
      return *this;
    }
const PROJ& addProjection ( const PROJ &  proj,
const std::string &  name 
) [inline, protected, inherited]

Register a contained projection (user-facing version)

Deprecated:
Use declareProjection() or declare()
Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 157 of file ProjectionApplier.hh.

{ return declareProjection(proj, name); }
const PROJ& apply ( const Event evt,
const Projection proj 
) const [inline, inherited]

Apply the supplied projection on event evt (user-facing alias).

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 80 of file ProjectionApplier.hh.

{ return applyProjection<PROJ>(evt, proj); }
const PROJ& apply ( const Event evt,
const PROJ &  proj 
) const [inline, inherited]

Apply the supplied projection on event evt (user-facing alias).

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 92 of file ProjectionApplier.hh.

{ return applyProjection<PROJ>(evt, proj); }
const PROJ& apply ( const Event evt,
const std::string &  name 
) const [inline, inherited]

Apply the supplied projection on event evt (user-facing alias).

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 104 of file ProjectionApplier.hh.

{ return applyProjection<PROJ>(evt, name); }
const PROJ& applyProjection ( const Event evt,
const Projection proj 
) const [inline, inherited]

Apply the supplied projection on event evt.

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 74 of file ProjectionApplier.hh.

                                                                                {
      return pcast<PROJ>(_applyProjection(evt, proj));
    }
const PROJ& applyProjection ( const Event evt,
const PROJ &  proj 
) const [inline, inherited]

Apply the supplied projection on event evt.

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 86 of file ProjectionApplier.hh.

                                                                          {
      return pcast<PROJ>(_applyProjection(evt, proj));
    }
const PROJ& applyProjection ( const Event evt,
const std::string &  name 
) const [inline, inherited]

Apply the named projection on event evt.

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 98 of file ProjectionApplier.hh.

                                                                               {
      return pcast<PROJ>(_applyProjection(evt, name));
    }
const set< PdgIdPair > beamPairs ( ) const [virtual, inherited]

Return the allowed beam pairs on which this projection can operate, not including recursion. Derived classes should ensure that all contained projections are registered in the _projections set for the beam constraint chaining to work.

Todo:
Remove the beam constraints system from projections.

Definition at line 35 of file Projection.cc.

                                                   {
    set<PdgIdPair> ret = _beamPairs;
    set<ConstProjectionPtr> projs = getProjections();
    for (set<ConstProjectionPtr>::const_iterator ip = projs.begin(); ip != projs.end(); ++ip) {
      ConstProjectionPtr p = *ip;
      getLog() << Log::TRACE << "Proj addr = " << p << endl;
      if (p) ret = intersection(ret, p->beamPairs());
    }
    return ret;
  }
bool before ( const Projection p) const [inherited]

Determine whether this object should be ordered before the object p given as argument. If p is of a different class than this, the before() function of the corresponding type_info objects is used. Otherwise, if the objects are of the same class, the virtual compare(const Projection &) will be returned.

Definition at line 24 of file Projection.cc.

                                                   {
    const std::type_info& thisid = typeid(*this);
    const std::type_info& otherid = typeid(p);
    if (thisid == otherid) {
      return compare(p) < 0;
    } else {
      return thisid.before(otherid);
    }
  }
double C ( ) const [inline]

Definition at line 74 of file ParisiTensor.hh.

{ return _C; }
void clear ( )

Clear the projection.

Definition at line 12 of file ParisiTensor.cc.

                           {
    _lambda[0] = 0;
    _lambda[1] = 0;
    _lambda[2] = 0;
    _C = 0;
    _D = 0;
  }
virtual unique_ptr<Projection> clone ( ) const [pure virtual, inherited]

Clone on the heap.

Implemented in JetAlg, AxesDefinition, and ParticleFinder.

int compare ( const Projection p) const [protected, virtual]

Compare with other projections.

Implements Projection.

Definition at line 7 of file ParisiTensor.cc.

                                                     {
    return mkNamedPCmp(p, "Sphericity");
  }
double D ( ) const [inline]

Definition at line 75 of file ParisiTensor.hh.

{ return _D; }
const PROJ& declare ( const PROJ &  proj,
const std::string &  name 
) [inline, protected, inherited]

Register a contained projection (user-facing version)

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 151 of file ProjectionApplier.hh.

{ return declareProjection(proj, name); }
const PROJ& declareProjection ( const PROJ &  proj,
const std::string &  name 
) [inline, protected, inherited]

Register a contained projection.

The type of the argument is used to instantiate a new projection internally: this new object is applied to events rather than the argument object. Hence you are advised to only use locally-scoped Projection objects in your Projection and Analysis constructors, and to avoid polymorphism (e.g. handling ConcreteProjection via a pointer or reference to type Projection) since this will screw up the internal type management.

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 142 of file ProjectionApplier.hh.

                                                                           {
      const Projection& reg = _declareProjection(proj, name);
      const PROJ& rtn = dynamic_cast<const PROJ&>(reg);
      return rtn;
    }

Clone on the heap.

const PROJ& get ( const std::string &  name) const [inline, inherited]

Get the named projection, specifying return type via a template argument (user-facing alias).

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 57 of file ProjectionApplier.hh.

{ return getProjection<PROJ>(name); }
Log& getLog ( ) const [inline, inherited]

Get a Log object based on the getName() property of the calling projection object.

Reimplemented from ProjectionApplier.

Definition at line 115 of file Projection.hh.

                        {
      string logname = "Rivet.Projection." + name();
      return Log::getLog(logname);
    }
const PROJ& getProjection ( const std::string &  name) const [inline, inherited]

Get the named projection, specifying return type via a template argument.

Todo:
Add SFINAE to require that PROJ inherit from Projection

Definition at line 50 of file ProjectionApplier.hh.

                                                           {
      const Projection& p = getProjHandler().getProjection(*this, name);
      return pcast<PROJ>(p);
    }
const Projection& getProjection ( const std::string &  name) const [inline, inherited]

Get the named projection (non-templated, so returns as a reference to a Projection base class).

Definition at line 61 of file ProjectionApplier.hh.

                                                                 {
      return getProjHandler().getProjection(*this, name);
    }
std::set<ConstProjectionPtr> getProjections ( ) const [inline, inherited]

Get the contained projections, including recursion.

Definition at line 43 of file ProjectionApplier.hh.

ProjectionHandler& getProjHandler ( ) const [inline, protected, inherited]

Get a reference to the ProjectionHandler for this thread.

Definition at line 122 of file ProjectionApplier.hh.

                                              {
      return _projhandler;
    }
double lambda1 ( ) const [inline]

Definition at line 80 of file ParisiTensor.hh.

{ return _lambda[0]; }
double lambda2 ( ) const [inline]

Definition at line 81 of file ParisiTensor.hh.

{ return _lambda[1]; }
double lambda3 ( ) const [inline]

Definition at line 82 of file ParisiTensor.hh.

{ return _lambda[2]; }
void markAsOwned ( ) const [inline, inherited]

Mark object as owned by the _projhandler

Todo:
Huh? What's this for?

Definition at line 111 of file ProjectionApplier.hh.

{ _owned = true; }
Cmp< Projection > mkNamedPCmp ( const Projection otherparent,
const std::string &  pname 
) const [protected, inherited]

Shortcut to make a named Cmp<Projection> comparison with the *this object automatically passed as one of the parent projections.

Definition at line 47 of file Projection.cc.

                                                                                                  {
    return pcmp(*this, otherparent, pname);
  }
Cmp< Projection > mkPCmp ( const Projection otherparent,
const std::string &  pname 
) const [protected, inherited]

Shortcut to make a named Cmp<Projection> comparison with the *this object automatically passed as one of the parent projections.

Note:
Alias for mkNamedPCmp

Definition at line 51 of file Projection.cc.

                                                                                             {
    return pcmp(*this, otherparent, pname);
  }
virtual std::string name ( ) const [inline, virtual, inherited]

Get the name of the projection.

Implements ProjectionApplier.

Definition at line 102 of file Projection.hh.

                                   {
      return _name;
    }
void project ( const Event e) [protected, virtual]

Perform the projection on the Event.

Implements Projection.

Definition at line 21 of file ParisiTensor.cc.

                                            {
    clear();

    // Apply sphericity projection to event
    Sphericity sph = applyProjection<Sphericity>(e, "Sphericity");

    // Set parameters
    _lambda[0] = sph.lambda1();
    _lambda[1] = sph.lambda2();
    _lambda[2] = sph.lambda3();
    _C = 3 * ( lambda1()*lambda2() + lambda1()*lambda3() + lambda2()*lambda3() );
    _D = 27 * lambda1() * lambda2() * lambda3();
  }
void setName ( const std::string &  name) [inline, inherited]

Used by derived classes to set their name.

Definition at line 121 of file Projection.hh.

                                        {
      _name = name;
    }

Friends And Related Function Documentation

friend class Cmp< Projection > [friend, inherited]

The Cmp specialization for Projection is a friend.

Definition at line 36 of file Projection.hh.

friend class Event [friend, inherited]

Event is a friend.

Definition at line 33 of file Projection.hh.


Member Data Documentation

bool _allowProjReg [protected, inherited]

Flag to forbid projection registration in analyses until the init phase.

Definition at line 176 of file ProjectionApplier.hh.

double _C [private]

The Parisi event shape variables.

Definition at line 89 of file ParisiTensor.hh.

double _D [private]

Definition at line 89 of file ParisiTensor.hh.

double _lambda[3] [private]

Eigenvalues.

Definition at line 92 of file ParisiTensor.hh.


The documentation for this class was generated from the following files: