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// Nsubjettiness Package
// Questions/Comments? jthaler@jthaler.net
//
// Copyright (c) 2011-14
// Jesse Thaler, Ken Van Tilburg, Christopher K. Vermilion, and TJ Wilkason
//
// $Id: Nsubjettiness.hh 822 2015-06-15 23:52:57Z jthaler $
//----------------------------------------------------------------------
// This file is part of FastJet contrib.
//
// It is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2 of the License, or (at
// your option) any later version.
//
// It is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
// License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this code. If not, see <http://www.gnu.org/licenses/>.
//----------------------------------------------------------------------
#ifndef __FASTJET_CONTRIB_NSUBJETTINESS_HH__
#define __FASTJET_CONTRIB_NSUBJETTINESS_HH__
#include <fastjet/internal/base.hh>
#include "Njettiness.hh"
#include "fastjet/FunctionOfPseudoJet.hh"
#include <string>
#include <climits>
FASTJET_BEGIN_NAMESPACE // defined in fastjet/internal/base.hh
namespace contrib {
// Classes defined in this file.
class Nsubjettiness;
class NsubjettinessRatio;
///------------------------------------------------------------------------
/// \class Nsubjettiness
/// \brief Implements the N-subjettiness jet shape
///
/**
* The N-jettiness jet shape.
*
* Nsubjettiness extends the concept of Njettiness to a jet shape, but other
* than the set of particles considered, they are identical. This class
* wraps the core Njettiness code to provide the fastjet::FunctionOfPseudoJet
* interface for convenience in larger analyses.
*
* The recommended AxesDefinitions are:
* KT_Axes : exclusive kt axes
* WTA_KT_Axes : exclusive kt with winner-take-all recombination
* OnePass_KT_Axes : one-pass minimization from kt starting point
* OnePass_WTA_KT_Axes : one-pass min. from wta_kt starting point
* More AxesDefinitions are listed in the README and defined in AxesDefinition.hh
*
* The recommended MeasureDefinitions are (with the corresponding parameters)
* NormalizedMeasure(beta,R0)
* : This was the original N-subjettiness measure (dimensionless)
* UnnormalizedMeasure(beta)
* : This is the new recommended default, same as above but without
* : the normalization factor, and hence has units of GeV
* NormalizedCutoffMeasure(beta,R0,Rcutoff)
* : Same as normalized_measure, but cuts off at Rcutoff
* UnnormalizedCutoffMeasure(beta,Rcutoff)
* : Same as unnormalized_measure, but cuts off at Rcutoff
* More MeasureDefinitions are listed in the README and defined in MeasureDefinition.hh
*
* For example, for the UnnormalizedMeasure(beta), N-subjettiness is defined as:
*
* tau_N = Sum_{i in jet} p_T^i min((DR_i1)^beta, (DR_i2)^beta, ...)
*
* DR_ij is the distance sqrt(Delta_phi^2 + Delta_rap^2) between particle i
* and jet j.
*
* The NormalizedMeausure include an extra parameter R0, and the various cutoff
* measures include an Rcutoff, which effectively defines an angular cutoff
* similar in effect to a cone-jet radius.
*/
class Nsubjettiness : public FunctionOfPseudoJet<double> {
public:
/// Main constructor, which takes N, the AxesDefinition, and the MeasureDefinition.
/// The Definitions are given in AxesDefinition.hh and MeasureDefinition.hh
Nsubjettiness(int N,
const AxesDefinition& axes_def,
const MeasureDefinition& measure_def)
: _njettinessFinder(axes_def,measure_def), _N(N) {}
/// Returns tau_N, measured on the constituents of this jet
double result(const PseudoJet& jet) const;
/// Returns components of tau_N, so that user can find individual tau values.
TauComponents component_result(const PseudoJet& jet) const;
/// To set axes in manual mode
void setAxes(const std::vector<fastjet::PseudoJet> & myAxes) {
// Note that cross check that manual mode has been set is in Njettiness
_njettinessFinder.setAxes(myAxes);
}
/// returns seed axes used for onepass minimization (otherwise same as currentAxes)
std::vector<fastjet::PseudoJet> seedAxes() const {
return _njettinessFinder.seedAxes();
}
/// returns current axes found by result() calculation
std::vector<fastjet::PseudoJet> currentAxes() const {
return _njettinessFinder.currentAxes();
}
/// returns subjet regions found by result() calculation (these have valid constituents)
/// Note that the axes and the subjets are not the same
std::vector<fastjet::PseudoJet> currentSubjets() const {
return _njettinessFinder.currentJets();
}
/// returns components of tau_N without recalculating anything
TauComponents currentTauComponents() const {
return _njettinessFinder.currentTauComponents();
}
/// returns components of tau_N without recalculating anything
TauPartition currentPartition() const {
return _njettinessFinder.currentPartition();
}
private:
/// Core Njettiness code that is called
Njettiness _njettinessFinder; // TODO: should muck with this so result can be const without this mutable
/// Number of subjets to find
int _N;
/// Warning if the user tries to use v1.0.3 constructor.
static LimitedWarning _old_constructor_warning;
public:
// The following interfaces are included for backwards compatibility, but no longer recommended.
// They may be deleted in a future release
/// \deprecated
/// Alternative constructors that define the measure via enums and parameters
/// These constructors will be removed in v3.0
/// Zero parameter arguments
/// (Currently, no measure uses this)
Nsubjettiness(int N,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode)
: _njettinessFinder(axes_mode, measure_mode, 0), _N(N) {
_old_constructor_warning.warn("Nsubjettiness: You are using the old style constructor. This is deprecated as of v2.1 and will be removed in v3.0. Please use the Nsubjettiness constructor based on AxesDefinition and MeasureDefinition instead.");
}
/// \deprecated
/// Construcotr for one parameter argument
/// (for unnormalized_measure, para1=beta)
Nsubjettiness(int N,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode,
double para1)
: _njettinessFinder(axes_mode, measure_mode, 1, para1), _N(N) {
_old_constructor_warning.warn("Nsubjettiness: You are using the old style constructor. This is deprecated as of v2.1 and will be removed in v3.0. Please use the Nsubjettiness constructor based on AxesDefinition and MeasureDefinition instead.");
}
/// \deprecated
/// Constructor for two parameter arguments
/// (for normalized_measure, para1=beta, para2=R0)
/// (for unnormalized_cutoff_measure, para1=beta, para2=Rcutoff)
Nsubjettiness(int N,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode,
double para1,
double para2)
: _njettinessFinder(axes_mode, measure_mode, 2, para1, para2), _N(N) {
_old_constructor_warning.warn("Nsubjettiness: You are using the old style constructor. This is deprecated as of v2.1 and will be removed in v3.0. Please use the Nsubjettiness constructor based on AxesDefinition and MeasureDefinition instead.");
}
/// \deprecated
/// Constructor for three parameter arguments
/// (for unnormalized_cutoff_measure, para1=beta, para2=R0, para3=Rcutoff)
Nsubjettiness(int N,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode,
double para1,
double para2,
double para3)
: _njettinessFinder(axes_mode, measure_mode, 3, para1, para2, para3), _N(N) {
_old_constructor_warning.warn("Nsubjettiness: You are using the old style constructor. This is deprecated as of v2.1 and will be removed in v3.0. Please use the Nsubjettiness constructor based on AxesDefinition and MeasureDefinition instead.");
}
/// \deprecated
/// Old constructor for backwards compatibility with v1.0,
/// where normalized_cutoff_measure was the only option
Nsubjettiness(int N,
Njettiness::AxesMode axes_mode,
double beta,
double R0,
double Rcutoff=std::numeric_limits<double>::max())
: _njettinessFinder(axes_mode, NormalizedCutoffMeasure(beta,R0,Rcutoff)), _N(N) {
_old_constructor_warning.warn("Nsubjettiness: You are using the old style constructor. This is deprecated as of v2.1 and will be removed in v3.0. Please use the Nsubjettiness constructor based on AxesDefinition and MeasureDefinition instead.");
}
};
///------------------------------------------------------------------------
/// \class NsubjettinessRatio
/// \brief Implements ratios of N-subjettiness jet shapes
///
/// NsubjettinessRatio uses the results from Nsubjettiness to calculate the ratio
/// tau_N/tau_M, where N and M are specified by the user. The ratio of different tau values
/// is often used in analyses, so this class is helpful to streamline code. Note that
/// manual axis mode is not supported
class NsubjettinessRatio : public FunctionOfPseudoJet<double> {
public:
/// Main constructor. Apart from specifying both N and M, the same options as Nsubjettiness
NsubjettinessRatio(int N,
int M,
const AxesDefinition & axes_def,
const MeasureDefinition & measure_def)
: _nsub_numerator(N,axes_def,measure_def),
_nsub_denominator(M,axes_def,measure_def) {
if (axes_def.needsManualAxes()) {
throw Error("NsubjettinessRatio does not support ManualAxes mode.");
}
}
/// Returns tau_N/tau_M based off the input jet using result function from Nsubjettiness
double result(const PseudoJet& jet) const;
private:
Nsubjettiness _nsub_numerator; ///< Function for numerator
Nsubjettiness _nsub_denominator; ///< Function for denominator
public:
// The following interfaces are included for backwards compatibility, but no longer recommended.
// They may be deprecated at some point.
/// \deprecated
/// Old-style constructor for zero arguments
/// Alternative constructor with enums and parameters
/// Again, likely to be removed
NsubjettinessRatio(int N,
int M,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode)
: _nsub_numerator(N, axes_mode, measure_mode),
_nsub_denominator(M, axes_mode, measure_mode) {}
/// \deprecated
/// Old-style constructor for one argument
NsubjettinessRatio(int N,
int M,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode,
double para1)
: _nsub_numerator(N, axes_mode, measure_mode, para1),
_nsub_denominator(M, axes_mode, measure_mode, para1) {}
/// \deprecated
/// Old-style constructor for 2 arguments
NsubjettinessRatio(int N,
int M,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode,
double para1,
double para2)
: _nsub_numerator(N, axes_mode, measure_mode, para1, para2),
_nsub_denominator(M, axes_mode, measure_mode, para1, para2) {}
/// \deprecated
/// Old-style constructor for 3 arguments
NsubjettinessRatio(int N,
int M,
Njettiness::AxesMode axes_mode,
Njettiness::MeasureMode measure_mode,
double para1,
double para2,
double para3)
: _nsub_numerator(N, axes_mode, measure_mode, para1, para2, para3),
_nsub_denominator(M, axes_mode, measure_mode, para1, para2, para3) {}
};
} // namespace contrib
FASTJET_END_NAMESPACE
#endif // __FASTJET_CONTRIB_NSUBJETTINESS_HH__

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