The Simple Genetic Algorithm with gray encoding (sga_gray) More...

#include <sga_gray.h>

Inheritance diagram for pagmo::algorithm::sga_gray:

Data Structures
struct	crossover
	Crossover operator info. More...

struct	mutation
	Mutation operator info. More...

struct	selection
	Selection info. More...

Public Member Functions
	sga_gray (int gen=1, const double &cr=.95, const double &m=.02, int elitism=1, mutation::type mut=mutation::UNIFORM, selection::type sel=selection::ROULETTE, crossover::type cro=crossover::SINGLE_POINT)
	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

The Simple Genetic Algorithm with gray encoding (sga_gray)

Simple Genetic algorithms are very popular algorithms used widely by people of very different backgrounds. Contrary to PAGMO::SGA, this implementation uses a binary encoding and some common mutation and crossover strategies.

Mutation is random, crossover uniform and selection is roulette or best20 (i.e. 20% best of the population is selected and reproduced 5 times).

The algorithm works on single objective, box constrained problems.

Author: Jeremie Labroquere (jerem.nosp@m.ie.l.nosp@m.abroq.nosp@m.uere.nosp@m.@gmai.nosp@m.l.co.nosp@m.m)

Definition at line 50 of file sga_gray.h.

Constructor & Destructor Documentation

pagmo::algorithm::sga_gray::sga_gray	(	int	gen = `1`,
		const double &	cr = `.95`,
		const double &	m = `.02`,
		int	elitism = `1`,
		mutation::type	mut = `mutation::UNIFORM`,
		selection::type	sel = `selection::ROULETTE`,
		crossover::type	cro = `crossover::SINGLE_POINT`
	)

Constructor.

Allows to specify in detail all the parameters of the algorithm.

Parameters

[in]	gen	Number of generations to evolve.
[in]	cr	Crossover probability (of each individual)
[in]	m	Mutation probability (of each encoded bit)
[in]	elitism	the best individual is reinserted in the population each elitism generations. If a elitism of 0 is set, then the elitism is avoided.
[in]	mut	Mutation type. sga_gray::mutation::UNIFORM
[in]	sel	Selection type. One of sga_gray::selection::BEST20, sga_gray::selection::ROULETTE
[in]	cro	Crossover type. One of sga_gray::crossover::SINGLE_POINT

Exceptions

value_error if gen is negative, crossover probability is not $\in [0,1]$ , mutation probability is not $\in [0,1]$ , elitism is <=0

Definition at line 59 of file sga_gray.cpp.

Member Function Documentation

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

virtual

Evolve implementation.

Run the simple genetic algorithm for the number of generations specified in the constructors. At each improvment velocity is also updated.

Parameters

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

We now set the cleared pop. cur_x is the best_x, re-evaluated with new seed.

Implements pagmo::algorithm::base.

Definition at line 92 of file sga_gray.cpp.

std::string pagmo::algorithm::sga_gray::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 233 of file sga_gray.cpp.

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

Data Structures

Public Member Functions

Protected Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation