Parameters to configure the computation of jet areas using ghosts. More...

#include <fastjet/GhostedAreaSpec.hh>

Collaboration diagram for fastjet::GhostedAreaSpec:

Public Member Functions
	GhostedAreaSpec ()
	default constructor
	GhostedAreaSpec (double ghost_maxrap_in, int repeat_in=gas::def_repeat, double ghost_area_in=gas::def_ghost_area, double grid_scatter_in=gas::def_grid_scatter, double pt_scatter_in=gas::def_pt_scatter, double mean_ghost_pt_in=gas::def_mean_ghost_pt)
	explicit constructor
	GhostedAreaSpec (double ghost_minrap_in, double ghost_maxrap_in, int repeat_in=gas::def_repeat, double ghost_area_in=gas::def_ghost_area, double grid_scatter_in=gas::def_grid_scatter, double pt_scatter_in=gas::def_pt_scatter, double mean_ghost_pt_in=gas::def_mean_ghost_pt)
	explicit constructor
	GhostedAreaSpec (const Selector &selector, int repeat_in=gas::def_repeat, double ghost_area_in=gas::def_ghost_area, double grid_scatter_in=gas::def_grid_scatter, double pt_scatter_in=gas::def_pt_scatter, double mean_ghost_pt_in=gas::def_mean_ghost_pt)
	constructor based on a Selector
void	_initialize ()
	does the initialization of actual ghost parameters
double	ghost_etamax () const
double	ghost_maxrap () const
double	ghost_area () const
double	grid_scatter () const
double	pt_scatter () const
double	mean_ghost_pt () const
int	repeat () const
bool	fj2_placement () const
double	kt_scatter () const
double	mean_ghost_kt () const
double	actual_ghost_area () const
int	n_ghosts () const
void	set_ghost_area (double val)
void	set_ghost_etamax (double val)
void	set_ghost_maxrap (double val)
void	set_grid_scatter (double val)
void	set_pt_scatter (double val)
void	set_mean_ghost_pt (double val)
void	set_repeat (int val)
void	set_kt_scatter (double val)
void	set_mean_ghost_kt (double val)
void	set_fj2_placement (bool val)
	if val is true, set ghost placement as it was in FastJet 2.X.
int	nphi () const
	return nphi (ghosts layed out (-nrap, 0..nphi-1), (-nrap+1,0..nphi-1), ...
int	nrap () const
void	get_random_status (std::vector< int > &__iseed) const
	get all relevant information about the status of the random number generator, so that it can be reset subsequently with set_random_status.
void	set_random_status (const std::vector< int > &__iseed)
	set the status of the random number generator, as obtained previously with get_random_status.
void	checkpoint_random ()
void	restore_checkpoint_random ()
std::string	description () const
	for a summary
void	add_ghosts (std::vector< PseudoJet > &) const
	push a set of ghost 4-momenta onto the back of the vector of PseudoJets
double	random_at_own_risk () const
	very deprecated public access to a random number from the internal generator
BasicRandom< double > &	generator_at_own_risk () const
	very deprecated public access to the generator itself

Detailed Description

Parameters to configure the computation of jet areas using ghosts.

Class that defines the parameters that go into the measurement of active jet areas.

Definition at line 62 of file GhostedAreaSpec.hh.

Constructor & Destructor Documentation

fastjet::GhostedAreaSpec::GhostedAreaSpec	(	const Selector &	selector,
		int	repeat_in = `gas::def_repeat`,
		double	ghost_area_in = `gas::def_ghost_area`,
		double	grid_scatter_in = `gas::def_grid_scatter`,
		double	pt_scatter_in = `gas::def_pt_scatter`,
		double	mean_ghost_pt_in = `gas::def_mean_ghost_pt`
	)		`[explicit]`

constructor based on a Selector

explicit constructor

Definition at line 42 of file GhostedAreaSpec.cc.

Member Function Documentation

void fastjet::GhostedAreaSpec::_initialize ( )

does the initialization of actual ghost parameters

sets the detailed parameters for the ghosts (which may not be quite the same as those requested -- this is in order for things to fit in nicely into 2pi etc...

Definition at line 85 of file GhostedAreaSpec.cc.

void fastjet::GhostedAreaSpec::set_fj2_placement ( bool val )

if val is true, set ghost placement as it was in FastJet 2.X.

The main differences between FJ2 and FJ3 ghost placement are

in FJ2 the rapidity spacing was ceil((maxrap-minrap)/sqrt(area)), while in FJ3 it is int((maxrap-minrap)/sqrt(area) + 0.5) [similarly for phi]. The FJ3 option offers more stability when trying to specify a spacing that exactly fits the extent.

in FJ2, the ghosts are placed at the corners of grid cells (i.e. extending up to maxrap), while in FJ3 they are placed at the centres of grid cells (i.e. extending roughly up to maxrap-sqrt(area)). The FJ2 behaviour effectively skews the total area coverage when maxrap is small, by an amount sqrt(area)/(2*maxrap).

FJ2 placement is now deprecated.

Definition at line 76 of file GhostedAreaSpec.cc.

int fastjet::GhostedAreaSpec::nphi ( ) const [inline]

return nphi (ghosts layed out (-nrap, 0..nphi-1), (-nrap+1,0..nphi-1), ...

(nrap,0..nphi-1)

Definition at line 173 of file GhostedAreaSpec.hh.

void fastjet::GhostedAreaSpec::get_random_status ( std::vector< int > & __iseed ) const [inline]

get all relevant information about the status of the random number generator, so that it can be reset subsequently with set_random_status.

Definition at line 179 of file GhostedAreaSpec.hh.

void fastjet::GhostedAreaSpec::set_random_status ( const std::vector< int > & __iseed ) [inline]

set the status of the random number generator, as obtained previously with get_random_status.

Note that the random generator is a static member of the class, i.e. common to all instances of the class --- so if you modify the random for this instance, you modify it for all instances.

Definition at line 187 of file GhostedAreaSpec.hh.

void fastjet::GhostedAreaSpec::add_ghosts ( std::vector< PseudoJet > & ) const

push a set of ghost 4-momenta onto the back of the vector of PseudoJets

adds the ghost 4-momenta to the vector of PseudoJet's

Definition at line 112 of file GhostedAreaSpec.cc.

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

include/fastjet/GhostedAreaSpec.hh
src/GhostedAreaSpec.cc

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation