deals with clustering More...

#include <fastjet/ClusterSequence.hh>

Inheritance diagram for fastjet::ClusterSequence:

Collaboration diagram for fastjet::ClusterSequence:

Classes
class	Extras
	base class to store extra information that plugins may provide More...

struct	history_element
	a single element in the clustering history More...

Public Types
enum	JetType { Invalid =-3, InexistentParent = -2, BeamJet = -1 }

typedef ClusterSequenceStructure	StructureType
	the structure type associated with a jet belonging to a ClusterSequence

Public Member Functions
	ClusterSequence ()
	default constructor

template<class L >
	ClusterSequence (const std::vector< L > &pseudojets, const JetDefinition &jet_def, const bool &writeout_combinations=false)
	create a ClusterSequence, starting from the supplied set of PseudoJets and clustering them with jet definition specified by jet_def (which also specifies the clustering strategy) More...

	ClusterSequence (const ClusterSequence &cs)
	copy constructor for a ClusterSequence

std::vector< PseudoJet >	inclusive_jets (const double ptmin=0.0) const
	return a vector of all jets (in the sense of the inclusive algorithm) with pt >= ptmin. More...

int	n_exclusive_jets (const double dcut) const
	return the number of jets (in the sense of the exclusive algorithm) that would be obtained when running the algorithm with the given dcut. More...

std::vector< PseudoJet >	exclusive_jets (const double dcut) const
	return a vector of all jets (in the sense of the exclusive algorithm) that would be obtained when running the algorithm with the given dcut. More...

std::vector< PseudoJet >	exclusive_jets (const int njets) const
	return a vector of all jets when the event is clustered (in the exclusive sense) to exactly njets. More...

std::vector< PseudoJet >	exclusive_jets_up_to (const int njets) const
	return a vector of all jets when the event is clustered (in the exclusive sense) to exactly njets. More...

double	exclusive_dmerge (const int njets) const
	return the dmin corresponding to the recombination that went from n+1 to n jets (sometimes known as d_{n n+1}). More...

double	exclusive_dmerge_max (const int njets) const
	return the maximum of the dmin encountered during all recombinations up to the one that led to an n-jet final state; identical to exclusive_dmerge, except in cases where the dmin do not increase monotonically. More...

double	exclusive_ymerge (int njets) const
	return the ymin corresponding to the recombination that went from n+1 to n jets (sometimes known as y_{n n+1}). More...

double	exclusive_ymerge_max (int njets) const
	same as exclusive_dmerge_max, but normalised to squared total energy

int	n_exclusive_jets_ycut (double ycut) const
	the number of exclusive jets at the given ycut

std::vector< PseudoJet >	exclusive_jets_ycut (double ycut) const
	the exclusive jets obtained at the given ycut

std::vector< PseudoJet >	exclusive_subjets (const PseudoJet &jet, const double dcut) const
	return a vector of all subjets of the current jet (in the sense of the exclusive algorithm) that would be obtained when running the algorithm with the given dcut. More...

int	n_exclusive_subjets (const PseudoJet &jet, const double dcut) const
	return the size of exclusive_subjets(...); still n ln n with same coefficient, but marginally more efficient than manually taking exclusive_subjets.size()

std::vector< PseudoJet >	exclusive_subjets (const PseudoJet &jet, int nsub) const
	return the list of subjets obtained by unclustering the supplied jet down to nsub subjets. More...

std::vector< PseudoJet >	exclusive_subjets_up_to (const PseudoJet &jet, int nsub) const
	return the list of subjets obtained by unclustering the supplied jet down to nsub subjets (or all constituents if there are fewer than nsub). More...

double	exclusive_subdmerge (const PseudoJet &jet, int nsub) const
	returns the dij that was present in the merging nsub+1 -> nsub subjets inside this jet. More...

double	exclusive_subdmerge_max (const PseudoJet &jet, int nsub) const
	returns the maximum dij that occurred in the whole event at the stage that the nsub+1 -> nsub merge of subjets occurred inside this jet. More...

double	Q () const
	returns the sum of all energies in the event (relevant mainly for e+e-)

double	Q2 () const
	return Q()^2

bool	object_in_jet (const PseudoJet &object, const PseudoJet &jet) const
	returns true iff the object is included in the jet. More...

bool	has_parents (const PseudoJet &jet, PseudoJet &parent1, PseudoJet &parent2) const
	if the jet has parents in the clustering, it returns true and sets parent1 and parent2 equal to them. More...

bool	has_child (const PseudoJet &jet, PseudoJet &child) const
	if the jet has a child then return true and give the child jet otherwise return false and set the child to zero

bool	has_child (const PseudoJet &jet, const PseudoJet *&childp) const
	Version of has_child that sets a pointer to the child if the child exists;.

bool	has_partner (const PseudoJet &jet, PseudoJet &partner) const
	if this jet has a child (and so a partner) return true and give the partner, otherwise return false and set the partner to zero

std::vector< PseudoJet >	constituents (const PseudoJet &jet) const
	return a vector of the particles that make up jet

void	print_jets_for_root (const std::vector< PseudoJet > &jets, std::ostream &ostr=std::cout) const
	output the supplied vector of jets in a format that can be read by an appropriate root script; the format is: jet-n jet-px jet-py jet-pz jet-E particle-n particle-rap particle-phi particle-pt particle-n particle-rap particle-phi particle-pt ... More...

void	print_jets_for_root (const std::vector< PseudoJet > &jets, const std::string &filename, const std::string &comment="") const
	print jets for root to the file labelled filename, with an optional comment at the beginning

void	add_constituents (const PseudoJet &jet, std::vector< PseudoJet > &subjet_vector) const
	add on to subjet_vector the constituents of jet (for internal use mainly)

Strategy	strategy_used () const
	return the enum value of the strategy used to cluster the event

std::string	strategy_string () const
	return the name of the strategy used to cluster the event

std::string	strategy_string (Strategy strategy_in) const
	return the name of the strategy associated with the enum strategy_in

const JetDefinition &	jet_def () const
	return a reference to the jet definition

void	delete_self_when_unused ()
	by calling this routine you tell the ClusterSequence to delete itself when all the Pseudojets associated with it have gone out of scope. More...

bool	will_delete_self_when_unused () const
	return true if the object has been told to delete itself when unused

void	signal_imminent_self_deletion () const
	tell the ClusterSequence it's about to be self deleted (internal use only)

double	jet_scale_for_algorithm (const PseudoJet &jet) const
	returns the scale associated with a jet as required for this clustering algorithm (kt^2 for the kt-algorithm, 1 for the Cambridge algorithm). More...

void	plugin_record_ij_recombination (int jet_i, int jet_j, double dij, int &newjet_k)
	record the fact that there has been a recombination between jets()[jet_i] and jets()[jet_k], with the specified dij, and return the index (newjet_k) allocated to the new jet, whose momentum is assumed to be the 4-vector sum of that of jet_i and jet_j

void	plugin_record_ij_recombination (int jet_i, int jet_j, double dij, const PseudoJet &newjet, int &newjet_k)
	as for the simpler variant of plugin_record_ij_recombination, except that the new jet is attributed the momentum and user_index of newjet

void	plugin_record_iB_recombination (int jet_i, double diB)
	record the fact that there has been a recombination between jets()[jet_i] and the beam, with the specified diB; when looking for inclusive jets, any iB recombination will returned to the user as a jet. More...

void	plugin_associate_extras (Extras *extras_in)
	the plugin can associate some extra information with the ClusterSequence object by calling this function. More...

void	plugin_associate_extras (std::auto_ptr< Extras > extras_in)
	the plugin can associate some extra information with the ClusterSequence object by calling this function More...

bool	plugin_activated () const
	returns true when the plugin is allowed to run the show.

const Extras *	extras () const
	returns a pointer to the extras object (may be null)

template<class GBJ >
void	plugin_simple_N2_cluster ()
	allows a plugin to run a templated clustering (nearest-neighbour heuristic) More...

const std::vector< PseudoJet > &	jets () const
	allow the user to access the internally stored _jets() array, which contains both the initial particles and the various intermediate and final stages of recombination. More...

const std::vector < history_element > &	history () const
	allow the user to access the raw internal history. More...

unsigned int	n_particles () const
	returns the number of particles that were provided to the clustering algorithm (helps the user find their way around the history and jets objects if they weren't paying attention beforehand). More...

std::vector< int >	particle_jet_indices (const std::vector< PseudoJet > &) const
	returns a vector of size n_particles() which indicates, for each of the initial particles (in the order in which they were supplied), which of the supplied jets it belongs to; if it does not belong to any of the supplied jets, the index is set to -1;

std::vector< int >	unique_history_order () const
	routine that returns an order in which to read the history such that clusterings that lead to identical jet compositions but different histories (because of degeneracies in the clustering order) will have matching constituents for each matching entry in the unique_history_order. More...

std::vector< PseudoJet >	unclustered_particles () const
	return the set of particles that have not been clustered. More...

std::vector< PseudoJet >	childless_pseudojets () const
	Return the list of pseudojets in the ClusterSequence that do not have children (and are not among the inclusive jets). More...

bool	contains (const PseudoJet &object) const
	returns true if the object (jet or particle) is contained by (ie belongs to) this cluster sequence. More...

void	transfer_from_sequence (const ClusterSequence &from_seq, const FunctionOfPseudoJet< PseudoJet > *action_on_jets=0)
	transfer the sequence contained in other_seq into our own; any plugin "extras" contained in the from_seq will be lost from there. More...

const SharedPtr < PseudoJetStructureBase > &	structure_shared_ptr () const
	retrieve a shared pointer to the wrapper to this ClusterSequence More...

template<>
void	_bj_set_jetinfo (EEBriefJet *const jetA, const int _jets_index) const

template<>
double	_bj_dist (const EEBriefJet const jeta, const EEBriefJet const jetb) const

Static Public Member Functions
static void	print_banner ()
	This is the function that is automatically called during clustering to print the FastJet banner. More...

static std::ostream *	fastjet_banner_stream ()
	returns a pointer to the stream to be used to print banners (cout by default). More...

Protected Member Functions
template<class L >
void	_transfer_input_jets (const std::vector< L > &pseudojets)
	transfer the vector<L> of input jets into our own vector<PseudoJet> _jets (with some reserved space for future growth). More...

void	_initialise_and_run (const JetDefinition &jet_def, const bool &writeout_combinations)
	This is what is called to do all the initialisation and then run the clustering (may be called by various constructors). More...

void	_initialise_and_run_no_decant ()

void	_decant_options (const JetDefinition &jet_def, const bool &writeout_combinations)
	fills in the various member variables with "decanted" options from the jet_definition and writeout_combinations variables

void	_decant_options_partial ()
	assuming that the jet definition, writeout_combinations and _structure_shared_ptr have been set (e.g. More...

void	_fill_initial_history ()
	fill out the history (and jet cross refs) related to the initial set of jets (assumed already to have been "transferred"), without any clustering

void	_do_ij_recombination_step (const int jet_i, const int jet_j, const double dij, int &newjet_k)
	carry out the recombination between the jets numbered jet_i and jet_j, at distance scale dij; return the index newjet_k of the result of the recombination of i and j. More...

void	_do_iB_recombination_step (const int jet_i, const double diB)
	carry out an recombination step in which _jets[jet_i] merges with the beam, More...

void	_set_structure_shared_ptr (PseudoJet &j)
	every time a jet is added internally during clustering, this should be called to set the jet's structure shared ptr to point to the CS (and the count of internally associated objects is also updated). More...

void	_update_structure_use_count ()
	make sure that the CS's internal tally of the use count matches that of the _structure_shared_ptr

Strategy	_best_strategy () const
	returns a suggestion for the best strategy to use on event multiplicity, algorithm, R, etc. More...

void	get_subhist_set (std::set< const history_element * > &subhist, const PseudoJet &jet, double dcut, int maxjet) const
	set subhist to be a set pointers to history entries corresponding to the subjets of this jet; one stops going working down through the subjets either when More...

Protected Attributes
JetDefinition	_jet_def

std::vector< PseudoJet >	_jets
	This contains the physical PseudoJets; for each PseudoJet one can find the corresponding position in the _history by looking at _jets[i].cluster_hist_index(). More...

std::vector< history_element >	_history
	this vector will contain the branching history; for each stage, _history[i].jetp_index indicates where to look in the _jets vector to get the physical PseudoJet. More...

bool	_writeout_combinations

int	_initial_n

double	_Rparam

double	_R2

double	_invR2

double	_Qtot

Strategy	_strategy

JetAlgorithm	_jet_algorithm

SharedPtr< PseudoJetStructureBase >	_structure_shared_ptr

int	_structure_use_count_after_construction

bool	_deletes_self_when_unused
	if true then the CS will delete itself when the last external object referring to it disappears. More...

Detailed Description

deals with clustering

Definition at line 61 of file ClusterSequence.hh.

Constructor & Destructor Documentation

template<class L >

fastjet::ClusterSequence::ClusterSequence	(	const std::vector< L > &	pseudojets,
		const JetDefinition &	jet_def,
		const bool &	writeout_combinations = `false`
	)

create a ClusterSequence, starting from the supplied set of PseudoJets and clustering them with jet definition specified by jet_def (which also specifies the clustering strategy)

constructor of a jet-clustering sequence from a vector of four-momenta, with the jet definition specified by jet_def

Definition at line 961 of file ClusterSequence.hh.

Member Function Documentation

vector< PseudoJet > fastjet::ClusterSequence::inclusive_jets ( const double ptmin = 0.0 ) const

return a vector of all jets (in the sense of the inclusive algorithm) with pt >= ptmin.

Time taken should be of the order of the number of jets returned.

Definition at line 864 of file ClusterSequence.cc.

int fastjet::ClusterSequence::n_exclusive_jets ( const double dcut ) const

return the number of jets (in the sense of the exclusive algorithm) that would be obtained when running the algorithm with the given dcut.

Definition at line 916 of file ClusterSequence.cc.

vector< PseudoJet > fastjet::ClusterSequence::exclusive_jets ( const double dcut ) const

return a vector of all jets (in the sense of the exclusive algorithm) that would be obtained when running the algorithm with the given dcut.

Definition at line 935 of file ClusterSequence.cc.

vector< PseudoJet > fastjet::ClusterSequence::exclusive_jets ( const int njets ) const

return a vector of all jets when the event is clustered (in the exclusive sense) to exactly njets.

If there are fewer than njets particles in the ClusterSequence an error is thrown

Definition at line 944 of file ClusterSequence.cc.

vector< PseudoJet > fastjet::ClusterSequence::exclusive_jets_up_to ( const int njets ) const

return a vector of all jets when the event is clustered (in the exclusive sense) to exactly njets.

If there are fewer than njets particles in the ClusterSequence the function just returns however many particles there were.

Definition at line 961 of file ClusterSequence.cc.

double fastjet::ClusterSequence::exclusive_dmerge ( const int njets ) const

return the dmin corresponding to the recombination that went from n+1 to n jets (sometimes known as d_{n n+1}).

return the dmin corresponding to the recombination that went from n+1 to n jets

If the number of particles in the event is <= njets, the function returns 0.

Definition at line 1029 of file ClusterSequence.cc.

double fastjet::ClusterSequence::exclusive_dmerge_max ( const int njets ) const

return the maximum of the dmin encountered during all recombinations up to the one that led to an n-jet final state; identical to exclusive_dmerge, except in cases where the dmin do not increase monotonically.

Definition at line 1041 of file ClusterSequence.cc.

double fastjet::ClusterSequence::exclusive_ymerge ( int njets ) const

inline

return the ymin corresponding to the recombination that went from n+1 to n jets (sometimes known as y_{n n+1}).

Definition at line 132 of file ClusterSequence.hh.

std::vector< PseudoJet > fastjet::ClusterSequence::exclusive_subjets	(	const PseudoJet &	jet,
		const double	dcut
	)		const

return a vector of all subjets of the current jet (in the sense of the exclusive algorithm) that would be obtained when running the algorithm with the given dcut.

Time taken is O(m ln m), where m is the number of subjets that are found. If m gets to be of order of the total number of constituents in the jet, this could be substantially slower than just getting that list of constituents.

Definition at line 1053 of file ClusterSequence.cc.

std::vector< PseudoJet > fastjet::ClusterSequence::exclusive_subjets	(	const PseudoJet &	jet,
		int	nsub
	)		const

return the list of subjets obtained by unclustering the supplied jet down to nsub subjets.

Throws an error if there are fewer than nsub particles in the jet.

This requires nsub ln nsub time

Throws an error if there are fewer than nsub particles in the jet.

Definition at line 1089 of file ClusterSequence.cc.

std::vector< PseudoJet > fastjet::ClusterSequence::exclusive_subjets_up_to	(	const PseudoJet &	jet,
		int	nsub
	)		const

return the list of subjets obtained by unclustering the supplied jet down to nsub subjets (or all constituents if there are fewer than nsub).

This requires nsub ln nsub time

Definition at line 1106 of file ClusterSequence.cc.

double fastjet::ClusterSequence::exclusive_subdmerge	(	const PseudoJet &	jet,
		int	nsub
	)		const

returns the dij that was present in the merging nsub+1 -> nsub subjets inside this jet.

return the dij that was present in the merging nsub+1 -> nsub subjets inside this jet.

Returns 0 if there were nsub or fewer constituents in the jet.

If the jet has nsub or fewer constituents, it will return 0.

will be zero if nconst <= nsub, since highest will be an original particle have zero dij

Definition at line 1134 of file ClusterSequence.cc.

double fastjet::ClusterSequence::exclusive_subdmerge_max	(	const PseudoJet &	jet,
		int	nsub
	)		const

returns the maximum dij that occurred in the whole event at the stage that the nsub+1 -> nsub merge of subjets occurred inside this jet.

return the maximum dij that occurred in the whole event at the stage that the nsub+1 -> nsub merge of subjets occurred inside this jet.

Returns 0 if there were nsub or fewer constituents in the jet.

If the jet has nsub or fewer constituents, it will return 0.

will be zero if nconst <= nsub, since highest will be an original particle have zero dij

Definition at line 1155 of file ClusterSequence.cc.

bool fastjet::ClusterSequence::object_in_jet	(	const PseudoJet &	object,
		const PseudoJet &	jet
	)		const

returns true iff the object is included in the jet.

NB: this is only sensible if the object is already registered within the cluster sequence, so you cannot use it with an input particle to the CS (since the particle won't have the history index set properly).

For nice clustering structures it should run in O(ln(N)) time but in worst cases (certain cone plugins) it can take O(n) time, where n is the number of particles in the jet.

Definition at line 1213 of file ClusterSequence.cc.

bool fastjet::ClusterSequence::has_parents	(	const PseudoJet &	jet,
		PseudoJet &	parent1,
		PseudoJet &	parent2
	)		const

if the jet has parents in the clustering, it returns true and sets parent1 and parent2 equal to them.

if it has no parents it returns false and sets parent1 and parent2 to zero

Definition at line 1239 of file ClusterSequence.cc.

void fastjet::ClusterSequence::print_jets_for_root	(	const std::vector< PseudoJet > &	jets,
		std::ostream &	ostr = `std::cout`
	)		const

output the supplied vector of jets in a format that can be read by an appropriate root script; the format is: jet-n jet-px jet-py jet-pz jet-E particle-n particle-rap particle-phi particle-pt particle-n particle-rap particle-phi particle-pt ...

#END ... [i.e. above repeated]

void fastjet::ClusterSequence::delete_self_when_unused ( )

by calling this routine you tell the ClusterSequence to delete itself when all the Pseudojets associated with it have gone out of scope.

At the time you call this, there must be at least one jet or other object outside the CS that is associated with the CS (e.g. the result of inclusive_jets()).

NB: after having made this call, the user is still allowed to delete the CS. Jets associated with it will then simply not be able to access their substructure after that point.

Definition at line 1716 of file ClusterSequence.cc.

double fastjet::ClusterSequence::jet_scale_for_algorithm ( const PseudoJet & jet ) const

returns the scale associated with a jet as required for this clustering algorithm (kt^2 for the kt-algorithm, 1 for the Cambridge algorithm).

Intended mainly for internal use and not valid for plugin algorithms.

Definition at line 567 of file ClusterSequence.cc.

void fastjet::ClusterSequence::plugin_record_iB_recombination	(	int	jet_i,
		double	diB
	)

inline

record the fact that there has been a recombination between jets()[jet_i] and the beam, with the specified diB; when looking for inclusive jets, any iB recombination will returned to the user as a jet.

Definition at line 333 of file ClusterSequence.hh.

void fastjet::ClusterSequence::plugin_associate_extras ( Extras * extras_in )

inline

the plugin can associate some extra information with the ClusterSequence object by calling this function.

The ClusterSequence takes ownership of the pointer (and responsibility for deleting it when the CS gets deleted).

Definition at line 355 of file ClusterSequence.hh.

void fastjet::ClusterSequence::plugin_associate_extras ( std::auto_ptr< Extras > extras_in )

inline

the plugin can associate some extra information with the ClusterSequence object by calling this function

As of FJ v3.1, this is deprecated, in line with the deprecation of auto_ptr in C++11

Definition at line 364 of file ClusterSequence.hh.

template<class GBJ >

void fastjet::ClusterSequence::plugin_simple_N2_cluster ( )

inline

allows a plugin to run a templated clustering (nearest-neighbour heuristic)

This has N^2 behaviour on "good" distance, but a worst case behaviour of N^3 (and many algs trigger the worst case behaviour)

For more details on how this works, see GenBriefJet below

Definition at line 381 of file ClusterSequence.hh.

const std::vector< PseudoJet > & fastjet::ClusterSequence::jets ( ) const

inline

allow the user to access the internally stored _jets() array, which contains both the initial particles and the various intermediate and final stages of recombination.

The first n_particles() entries are the original particles, in the order in which they were supplied to the ClusterSequence constructor. It can be useful to access them for example when examining whether a given input object is part of a specific jet, via the objects_in_jet(...) member function (which only takes PseudoJets that are registered in the ClusterSequence).

One of the other (internal uses) is related to the fact because we don't seem to be able to access protected elements of the class for an object that is not "this" (at least in case where "this" is of a slightly different kind from the object, both derived from ClusterSequence).

Definition at line 980 of file ClusterSequence.hh.

const std::vector< ClusterSequence::history_element > & fastjet::ClusterSequence::history ( ) const

inline

allow the user to access the raw internal history.

This is present (as for jets()) in part so that protected derived classes can access this information about other ClusterSequences.

A user who wishes to follow the details of the ClusterSequence can also make use of this information (and should consult the history_element documentation for more information), but should be aware that these internal structures may evolve in future FastJet versions.

Definition at line 984 of file ClusterSequence.hh.

unsigned int fastjet::ClusterSequence::n_particles ( ) const

inline

returns the number of particles that were provided to the clustering algorithm (helps the user find their way around the history and jets objects if they weren't paying attention beforehand).

Definition at line 988 of file ClusterSequence.hh.

vector< int > fastjet::ClusterSequence::unique_history_order ( ) const

routine that returns an order in which to read the history such that clusterings that lead to identical jet compositions but different histories (because of degeneracies in the clustering order) will have matching constituents for each matching entry in the unique_history_order.

The order has the property that an entry's parents will always appear prior to that entry itself.

Roughly speaking the order is such that we first provide all steps that lead to the final jet containing particle 1; then we have the steps that lead to reconstruction of the jet containing the next-lowest-numbered unclustered particle, etc... [see GPS CCN28-12 for more info – of course a full explanation here would be better...]

Definition at line 1516 of file ClusterSequence.cc.

vector< PseudoJet > fastjet::ClusterSequence::unclustered_particles ( ) const

return the set of particles that have not been clustered.

For kt and cam/aachen algorithms this should always be null, but for cone type algorithms it can be non-null;

Definition at line 1571 of file ClusterSequence.cc.

vector< PseudoJet > fastjet::ClusterSequence::childless_pseudojets ( ) const

Return the list of pseudojets in the ClusterSequence that do not have children (and are not among the inclusive jets).

They may result from a clustering step or may be one of the pseudojets returned by unclustered_particles().

Definition at line 1585 of file ClusterSequence.cc.

bool fastjet::ClusterSequence::contains ( const PseudoJet & object ) const

returns true if the object (jet or particle) is contained by (ie belongs to) this cluster sequence.

Tests performed: if thejet's interface is this cluster sequence and its cluster history index is in a consistent range.

Definition at line 1600 of file ClusterSequence.cc.

void fastjet::ClusterSequence::transfer_from_sequence	(	const ClusterSequence &	from_seq,
		const FunctionOfPseudoJet< PseudoJet > *	action_on_jets = `0`
	)

transfer the sequence contained in other_seq into our own; any plugin "extras" contained in the from_seq will be lost from there.

It also sets the ClusterSequence pointers of the PseudoJets in the history to point to this ClusterSequence

When specified, the second argument is an action that will be applied on every jets in the resulting ClusterSequence

Definition at line 787 of file ClusterSequence.cc.

const SharedPtr<PseudoJetStructureBase>& fastjet::ClusterSequence::structure_shared_ptr ( ) const

inline

retrieve a shared pointer to the wrapper to this ClusterSequence

this may turn useful if you want to track when this ClusterSequence goes out of scope

Definition at line 527 of file ClusterSequence.hh.

void fastjet::ClusterSequence::print_banner ( )

static

This is the function that is automatically called during clustering to print the FastJet banner.

Only the first call to this function will result in the printout of the banner. Users may wish to call this function themselves, during the initialization phase of their program, in order to ensure that the banner appears before other output. This call will not affect 3rd-party banners, e.g. those from plugins.

Definition at line 423 of file ClusterSequence.cc.

static std::ostream* fastjet::ClusterSequence::fastjet_banner_stream ( )

inlinestatic

returns a pointer to the stream to be used to print banners (cout by default).

This function is used by plugins to determine where to direct their banners. Plugins should properly handle the case where the pointer is null.

Definition at line 564 of file ClusterSequence.hh.

template<class L >

void fastjet::ClusterSequence::_transfer_input_jets ( const std::vector< L > & pseudojets )

protected

transfer the vector<L> of input jets into our own vector<PseudoJet> _jets (with some reserved space for future growth).

Definition at line 925 of file ClusterSequence.hh.

void fastjet::ClusterSequence::_initialise_and_run	(	const JetDefinition &	jet_def,
		const bool &	writeout_combinations
	)

protected

This is what is called to do all the initialisation and then run the clustering (may be called by various constructors).

It assumes _jets contains the momenta to be clustered.

Definition at line 207 of file ClusterSequence.cc.

void fastjet::ClusterSequence::_decant_options_partial ( )

protected

assuming that the jet definition, writeout_combinations and _structure_shared_ptr have been set (e.g.

in an initialiser list in the constructor), it handles the remaining decanting of options.

Definition at line 469 of file ClusterSequence.cc.

void fastjet::ClusterSequence::_do_ij_recombination_step	(	const int	jet_i,
		const int	jet_j,
		const double	dij,
		int &	newjet_k
	)

protected

carry out the recombination between the jets numbered jet_i and jet_j, at distance scale dij; return the index newjet_k of the result of the recombination of i and j.

carries out the bookkeeping associated with the step of recombining jet_i and jet_j (assuming a distance dij) and returns the index of the recombined jet, newjet_k.

Definition at line 1643 of file ClusterSequence.cc.

void fastjet::ClusterSequence::_do_iB_recombination_step	(	const int	jet_i,
		const double	diB
	)

protected

carry out an recombination step in which _jets[jet_i] merges with the beam,

carries out the bookkeeping associated with the step of recombining jet_i with the beam

Definition at line 1680 of file ClusterSequence.cc.

void fastjet::ClusterSequence::_set_structure_shared_ptr ( PseudoJet & j )

protected

every time a jet is added internally during clustering, this should be called to set the jet's structure shared ptr to point to the CS (and the count of internally associated objects is also updated).

This should not be called outside construction of a CS object.

Definition at line 1697 of file ClusterSequence.cc.

Strategy fastjet::ClusterSequence::_best_strategy ( ) const

protected

returns a suggestion for the best strategy to use on event multiplicity, algorithm, R, etc.

Definition at line 603 of file ClusterSequence.cc.

void fastjet::ClusterSequence::get_subhist_set	(	std::set< const history_element * > &	subhist,
		const PseudoJet &	jet,
		double	dcut,
		int	maxjet
	)		const

protected

set subhist to be a set pointers to history entries corresponding to the subjets of this jet; one stops going working down through the subjets either when

return a set of pointers to history entries corresponding to the subjets of this jet; one stops going working down through the subjets either when

there is no further to go
one has found maxjet entries
max_dij_so_far <= dcut By setting maxjet=0 one can use just dcut; by setting dcut<0 one can use jet maxjet
there is no further to go
one has found maxjet entries
max_dij_so_far <= dcut

Definition at line 1179 of file ClusterSequence.cc.

Member Data Documentation

std::vector<PseudoJet> fastjet::ClusterSequence::_jets

protected

This contains the physical PseudoJets; for each PseudoJet one can find the corresponding position in the _history by looking at _jets[i].cluster_hist_index().

Definition at line 672 of file ClusterSequence.hh.

std::vector<history_element> fastjet::ClusterSequence::_history

protected

this vector will contain the branching history; for each stage, _history[i].jetp_index indicates where to look in the _jets vector to get the physical PseudoJet.

Definition at line 678 of file ClusterSequence.hh.

bool fastjet::ClusterSequence::_deletes_self_when_unused

mutableprotected

if true then the CS will delete itself when the last external object referring to it disappears.

It is mutable so as to ensure that signal_imminent_self_deletion() [const] can make relevant changes.

Definition at line 704 of file ClusterSequence.hh.

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

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Static Public Member Functions

Protected Member Functions

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Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation