Rivet/Projections/FParameter.hh

0001 // -*- C++ -*-
0002 #ifndef RIVET_FParameter_HH
0003 #define RIVET_FParameter_HH
0004
0005 #include "Rivet/Projection.hh"
0006 #include "Rivet/Projections/FinalState.hh"
0007 #include "Rivet/Event.hh"
0008
0009 namespace Rivet {
0010
0011
0012   /// Calculator of the @f$ F @f$-parameter observable
0013   class FParameter : public Projection {
0014   public:
0015
0016     /// @name Constructors etc.
0017     /// @{
0018
0019     /// Constructor
0020     FParameter(const FinalState& fsp);
0021
0022     /// Clone on the heap.
0023     RIVET_DEFAULT_PROJ_CLONE(FParameter);
0024
0025     /// @}
0026
0027     /// Import to avoid warnings about overload-hiding
0028     using Projection::operator =;
0029
0030
0031   protected:
0032
0033     /// Perform the projection on the Event
0034     void project(const Event& e);
0035
0036     /// Compare with other projections
0037     //CmpState compare(const Projection& p) const;
0038     // Taken from Thrust.hh
0039     CmpState compare(const Projection& p) const {
0040       return mkNamedPCmp(p, "FS");
0041     }
0042
0043
0044   public:
0045
0046     /// Reset the projection
0047     void clear();
0048
0049     /// @name Access the event shapes by name
0050     /// @{
0051     /// F-Parametr
0052     double F() const { return lambda1() >= lambda2() ? lambda2()/lambda1() : lambda1()/lambda2(); }
0053     /// @}
0054
0055     /// @name Access the linearised transverse momentum tensor eigenvalues
0056     /// @{
0057     double lambda1() const { return _lambdas[0]; }
0058     double lambda2() const { return _lambdas[1]; }
0059     /// @}
0060
0061
0062     /// @name Direct methods
0063     /// Ways to do the calculation directly, without engaging the caching system
0064     /// @{
0065
0066     /// Manually calculate the sphericity, without engaging the caching system
0067     void calc(const FinalState& fs);
0068
0069     /// Manually calculate the sphericity, without engaging the caching system
0070     void calc(const vector<Particle>& fsparticles);
0071
0072     /// Manually calculate the sphericity, without engaging the caching system
0073     void calc(const vector<FourMomentum>& fsmomenta);
0074
0075     /// Manually calculate the sphericity, without engaging the caching system
0076     void calc(const vector<Vector3>& fsmomenta);
0077
0078     /// @}
0079
0080
0081   protected:
0082
0083     /// Eigenvalues
0084     vector<double> _lambdas;
0085
0086
0087   protected:
0088
0089     /// Actually do the calculation
0090     void _calcFParameter(const vector<Vector3>& fsmomenta);
0091
0092   };
0093
0094
0095 }
0096
0097 #endif