Non-dominated Sorting Particle Swarm Optimizer (NSPSO) More...

#include <nspso.h>

Inheritance diagram for pagmo::algorithm::nspso:

Public Types
enum	diversity_mechanism_type { CROWDING_DISTANCE =0, NICHE_COUNT =1, MAXMIN =2 }
	Mechanism used to asses diversity. More...

Public Member Functions
	nspso (int gen=100, double minW=0.4, double maxW=1.0, double C1=2.0, double C2=2.0, double CHI=1.0, double v_coeff=0.5, int leader_selection_range=10, diversity_mechanism_type=CROWDING_DISTANCE)
	Constructor. More...

base_ptr	clone () const
	Clone method.

void	evolve (population &) const
	Evolve implementation. More...

std::string	get_name () const
	Algorithm name.

Public Member Functions inherited from pagmo::algorithm::base
	base ()
	Default constructor. More...

virtual	~base ()
	Trivial destructor. More...

std::string	human_readable () const
	Return human readable representation of the algorithm. More...

void	set_screen_output (const bool p)
	Setter-Getter for protected m_screen_output data. More...

bool	get_screen_output () const
	Gets screen output. More...

void	reset_rngs (const unsigned int) const
	Resets the seed of the internal rngs using a user-provided seed. More...

Protected Member Functions
std::string	human_readable_extra () const
	Extra human readable algorithm info. More...

Friends
class	boost::serialization::access

Additional Inherited Members
Protected Attributes inherited from pagmo::algorithm::base
bool	m_screen_output
	Indicates to the derived class whether to print stuff on screen.

rng_double	m_drng
	Random number generator for double-precision floating point values.

rng_uint32	m_urng
	Random number generator for unsigned integer values.

unsigned int	m_fevals
	A counter for the number of function evaluations.

Detailed Description

Non-dominated Sorting Particle Swarm Optimizer (NSPSO)

Non-dominated Sorting Particle Swarm Optimizer (NSPSO) is a modified version of PSO for multi-objective optimization. It extends the basic ideas of PSO by making a better use of personal bests and offspring for non-dominated comparison. In order to increase the diversity of the pareto front it is possible to choose between 3 different niching methods: crowding distance, niche count and maxmin.

Author: Andrea Mambrini (andre.nosp@m.a.ma.nosp@m.mbrin.nosp@m.i@gm.nosp@m.ail.c.nosp@m.om); Annalisa Riccardi (nina1.nosp@m.983@.nosp@m.gmail.nosp@m..com)

See also: "Xiaodong Li - A Non-dominated Sorting Particle Swarm Optimizer for Multiobjective Optimization"; "Xiaodong Li - Better Spread and Convergence: Particle Swarm Multiobjective Optimization Using the Maximin Fitness Function"; "Carlos M. Fonseca, Peter J. Fleming - Genetic Algorithms for Multiobjective Optimization: Formulation, Discussion and Generalization"

Definition at line 51 of file nspso.h.

Member Enumeration Documentation

enum pagmo::algorithm::nspso::diversity_mechanism_type

Mechanism used to asses diversity.

Enumerator
CROWDING_DISTANCE	The crowding distance is used.
NICHE_COUNT	The ....
MAXMIN	The ....

Definition at line 55 of file nspso.h.

Constructor & Destructor Documentation

pagmo::algorithm::nspso::nspso	(	int	gen = `100`,
		double	minW = `0.4`,
		double	maxW = `1.0`,
		double	C1 = `2.0`,
		double	C2 = `2.0`,
		double	CHI = `1.0`,
		double	v_coeff = `0.5`,
		int	leader_selection_range = `10`,
		diversity_mechanism_type	diversity_mechanism = `CROWDING_DISTANCE`
	)

Constructor.

Constructs a NSPSO algorithm (multi objective PSO)

Parameters

[in]	gen	Number of generations to evolve.
[in]	minW	minimum particles' inertia weight (the inertia weight is decreased troughout the run between maxW and minW)
[in]	maxW	maximum particles' inertia weight (the inertia weight is decreased troughout the run between maxW and minW)
[in]	C1	magnitude of the force, applied to the particle's velocity, in the direction of its previous best position
[in]	C2	magnitude of the force, applied to the particle's velocity, in the direction of its global best (leader)
[in]	CHI	velocity scaling factor
[in]	v_coeff	velocity coefficient (determining the maximum allowed particle velocity)
[in]	leader_selection_range	the leader of each particle is selected among the best leader_selection_range% individuals
[in]	diversity_mechanism	the diversity mechanism to use to mantein diversity on the pareto front

Exceptions

value_error if gen is negative

Definition at line 62 of file nspso.cpp.

Member Function Documentation

void pagmo::algorithm::nspso::evolve ( population & pop ) const

virtual

Evolve implementation.

Run the NSPSO algorithm for the number of generations specified in the constructors.

Parameters

[in,out] pop input/output pagmo::population to be evolved.

Implements pagmo::algorithm::base.

Definition at line 109 of file nspso.cpp.

std::string pagmo::algorithm::nspso::human_readable_extra ( ) const

protectedvirtual

Extra human readable algorithm info.

Will return a formatted string displaying the parameters of the algorithm.

Reimplemented from pagmo::algorithm::base.

Definition at line 593 of file nspso.cpp.

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

Public Types

Public Member Functions

Protected Member Functions

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation