class that is intended to hold a full definition of the jet clusterer More...

#include <JetDefinition.hh>

Collaboration diagram for fastjet::JetDefinition:

Classes
class	DefaultRecombiner
	A class that will provide the recombination scheme facilities and/or allow a user to extend these facilities. More...
class	Plugin
	a class that allows a user to introduce their own "plugin" jet finder More...
class	Recombiner
	An abstract base class that will provide the recombination scheme facilities and/or allow a user to extend these facilities. More...
Public Member Functions
	JetDefinition (JetAlgorithm jet_algorithm, double R, RecombinationScheme recomb_scheme=E_scheme, Strategy strategy=Best)
	constructor with alternative ordering or arguments -- note that we have not provided a default jet finder, to avoid ambiguous JetDefinition() constructor.
	JetDefinition (JetAlgorithm jet_algorithm, RecombinationScheme recomb_scheme=E_scheme, Strategy strategy=Best)
	constructor for algorithms that have no free parameters (e.g.
	JetDefinition (JetAlgorithm jet_algorithm, double R, double xtra_param, RecombinationScheme recomb_scheme=E_scheme, Strategy strategy=Best)
	constructor for algorithms that require R + one extra parameter to be set (the gen-kt series for example)
	JetDefinition (JetAlgorithm jet_algorithm, double R, const Recombiner *recombiner, Strategy strategy=Best)
	constructor in a form that allows the user to provide a pointer to an external recombiner class (which must remain valid for the life of the JetDefinition object).
	JetDefinition (JetAlgorithm jet_algorithm, const Recombiner *recombiner, Strategy strategy=Best)
	constructor for case with 0 parameters (ee_kt_algorithm) and and external recombiner
	JetDefinition (JetAlgorithm jet_algorithm, double R, double xtra_param, const Recombiner *recombiner, Strategy strategy=Best)
	constructor allowing the extra parameter to be set and a pointer to a recombiner
	JetDefinition ()
	a default constructor
	JetDefinition (const Plugin *plugin)
	constructor based on a pointer to a user's plugin; the object pointed to must remain valid for the whole duration of existence of the JetDefinition and any related ClusterSequences
	JetDefinition (JetAlgorithm jet_algorithm, double R, Strategy strategy, RecombinationScheme recomb_scheme=E_scheme, int nparameters=1)
	constructor to fully specify a jet-definition (together with information about how algorithically to run it).
void	set_recombination_scheme (RecombinationScheme)
	set the recombination scheme to the one provided
void	set_recombiner (const Recombiner *recomb)
	set the recombiner class to the one provided
const Plugin *	plugin () const
	return a pointer to the plugin
JetAlgorithm	jet_algorithm () const
	return information about the definition...
JetAlgorithm	jet_finder () const
	same as above for backward compatibility
double	R () const
double	extra_param () const
Strategy	strategy () const
RecombinationScheme	recombination_scheme () const
void	set_jet_algorithm (JetAlgorithm njf)
	(re)set the jet finder
void	set_jet_finder (JetAlgorithm njf)
	same as above for backward compatibility
void	set_extra_param (double xtra_param)
	(re)set the general purpose extra parameter
const Recombiner *	recombiner () const
	return a pointer to the currently defined recombiner.
std::string	description () const
	return a textual description of the current jet definition

Detailed Description

class that is intended to hold a full definition of the jet clusterer

Definition at line 172 of file JetDefinition.hh.

Constructor & Destructor Documentation

fastjet::JetDefinition::JetDefinition	(	JetAlgorithm	jet_algorithm,
		double	R,
		RecombinationScheme	recomb_scheme = `E_scheme`,
		Strategy	strategy = `Best`
	)			`[inline]`

constructor with alternative ordering or arguments -- note that we have not provided a default jet finder, to avoid ambiguous JetDefinition() constructor.

Definition at line 190 of file JetDefinition.hh.

                                          {
    *this = JetDefinition(jet_algorithm, R, strategy, recomb_scheme, 1);
  }

fastjet::JetDefinition::JetDefinition	(	JetAlgorithm	jet_algorithm,
		RecombinationScheme	recomb_scheme = `E_scheme`,
		Strategy	strategy = `Best`
	)			`[inline]`

constructor for algorithms that have no free parameters (e.g.

ee_kt_algorithm)

Definition at line 199 of file JetDefinition.hh.

                                          {
    double dummyR = 0.0;
    *this = JetDefinition(jet_algorithm, dummyR, strategy, recomb_scheme, 0);
  }

fastjet::JetDefinition::JetDefinition	(	JetAlgorithm	jet_algorithm,
		double	R,
		const Recombiner *	recombiner,
		Strategy	strategy = `Best`
	)			`[inline]`

constructor in a form that allows the user to provide a pointer to an external recombiner class (which must remain valid for the life of the JetDefinition object).

Definition at line 221 of file JetDefinition.hh.

References fastjet::external_scheme.

                                          {
    *this = JetDefinition(jet_algorithm, R, external_scheme, strategy);
    _recombiner = recombiner;
  }

fastjet::JetDefinition::JetDefinition	(	JetAlgorithm	jet_algorithm,
		double	R,
		Strategy	strategy,
		RecombinationScheme	recomb_scheme = `E_scheme`,
		int	nparameters = `1`
	)

constructor to fully specify a jet-definition (together with information about how algorithically to run it).

the ordering of arguments here is old and deprecated (except as the common constructor for internal use)

Definition at line 42 of file JetDefinition.cc.

References fastjet::ee_genkt_algorithm, fastjet::ee_kt_algorithm, fastjet::genkt_algorithm, fastjet::plugin_strategy, set_extra_param(), and set_recombination_scheme().

                                              :
  _jet_algorithm(jet_algorithm), _Rparam(R), _strategy(strategy) {

  // set R parameter or ensure its sensibleness, as appropriate
  if (jet_algorithm == ee_kt_algorithm) {
    _Rparam = 4.0; // introduce a fictional R that ensures that
                   // our clustering sequence will not produce
                   // "beam" jets except when only a single particle remains.
                   // Any value > 2 would have done here
  } else {
    // We maintain some limit on R because particles with pt=0, m=0
    // can have rapidities O(10000) and one doesn't want the
    // clustering to start including them as if their rapidities were
    // physical.
    assert ( R < 1000.0);
  }

  // cross-check the number of parameters that were declared in setting up the
  // algorithm (passed internally from the public constructors)
  ostringstream oss;
  switch (jet_algorithm) {
  case ee_kt_algorithm:
    if (nparameters != 0) oss << "ee_kt_algorithm should be constructed with 0 parameters but was called with " 
                              << nparameters << " parameter(s)\n";
    break;
  case genkt_algorithm: 
  case ee_genkt_algorithm: 
    if (nparameters != 2) oss << "(ee_)genkt_algorithm should be constructed with 2 parameters but was called with " 
                              << nparameters << " parameter(s)\n";
    break;
  default:
    if (nparameters != 1)
    oss << "The jet algorithm you requested ("
        << jet_algorithm << ") should be constructed with 1 parameter but was called with " 
        << nparameters << " parameter(s)\n";
  }
  if (oss.str() != "") throw Error(oss.str()); 

  // make sure the strategy requested is sensible
  assert (_strategy  != plugin_strategy);

  _plugin = NULL;
  set_recombination_scheme(recomb_scheme);
  set_extra_param(0.0); // make sure it's defined
}

Member Function Documentation

const Recombiner* fastjet::JetDefinition::recombiner ( ) const [inline]

return a pointer to the currently defined recombiner.

Warning: the pointer may be to an internal recombiner (for default recombination schemes), in which case if the JetDefinition becomes invalid (e.g. is deleted), the pointer will then point to an object that no longer exists.

Note also that if you copy a JetDefinition with a default recombination scheme, then the two copies will have distinct recombiners, and return different recombiner() pointers.

Definition at line 332 of file JetDefinition.hh.

Referenced by description().

                                        {
    return _recombiner == 0 ? & _default_recombiner : _recombiner;}

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

include/fastjet/JetDefinition.hh
src/JetDefinition.cc

fastjet::JetDefinition Class Reference [Fundamental FastJet classes]

Classes

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

fastjet::JetDefinition Class Reference
[Fundamental FastJet classes]