Core

This subpackage store templates used in jMetalPy.

Algorithm

class jmetal.core.algorithm.Algorithm

Bases: typing.Generic, threading.Thread

get_current_computing_time() → float

get_evaluations() → int

get_name() → str

get_result() → R

Returns:Final population.

class jmetal.core.algorithm.EvolutionaryAlgorithm

Bases: jmetal.core.algorithm.Algorithm

create_initial_population() → typing.List[S]

evaluate_population(population: typing.List[S]) → typing.List[S]

init_progress() → None

is_stopping_condition_reached() → bool

replacement(population: typing.List[S], offspring_population: typing.List[S]) → typing.List[S]

reproduction(population: typing.List[S]) → typing.List[S]

run()

• Step One: Generate the initial population of individuals randomly. (First generation)

• Step Two: Evaluate the fitness of each individual in that population

• Step Three: Repeat the following regenerational steps until termination

  1. Select the best-fit individuals for reproduction. (Parents)
  2. Breed new individuals through crossover and mutation operations to give birth to offspring.
  3. Evaluate the individual fitness of new individuals.
  4. Replace least-fit population with new individuals.

Note

To develop an EA, all the abstract the methods used in the run() method must be implemented.

selection(population: typing.List[S]) → typing.List[S]

update_progress()

class jmetal.core.algorithm.ParticleSwarmOptimization

Bases: jmetal.core.algorithm.Algorithm

create_initial_swarm() → typing.List[jmetal.core.solution.FloatSolution]

evaluate_swarm(swarm: typing.List[jmetal.core.solution.FloatSolution]) → typing.List[jmetal.core.solution.FloatSolution]

init_progress() → None

initialize_global_best(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

initialize_particle_best(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

initialize_velocity(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

is_stopping_condition_reached() → bool

perturbation(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

run()

update_global_best(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

update_particle_best(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

update_position(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

update_progress() → None

update_velocity(swarm: typing.List[jmetal.core.solution.FloatSolution]) → None

jmetal.core.algorithm.R = ~R

Operator

class jmetal.core.operator.Crossover(probability: float)

Bases: jmetal.core.operator.Operator

Class representing crossover operator.

execute(source: S) → R

get_name() → str

get_number_of_parents()

class jmetal.core.operator.Mutation(probability: float)

Bases: jmetal.core.operator.Operator

Class representing mutation operator.

execute(source: S) → R

get_name() → str

class jmetal.core.operator.Operator

Bases: typing.Generic

Class representing operator

execute(source: S) → R

get_name() → str

jmetal.core.operator.R = ~R

class jmetal.core.operator.Selection

Bases: jmetal.core.operator.Operator

Class representing selection operator.

execute(source: S) → R

get_name() → str

Problem

class jmetal.core.problem.BinaryProblem(rf_path: str = None)

Bases: jmetal.core.problem.Problem

Class representing binary problems.

create_solution() → jmetal.core.solution.BinarySolution

evaluate(solution: jmetal.core.solution.BinarySolution) → jmetal.core.solution.BinarySolution

class jmetal.core.problem.FloatProblem(rf_path: str = None)

Bases: jmetal.core.problem.Problem

Class representing float problems.

create_solution() → jmetal.core.solution.FloatSolution

evaluate(solution: jmetal.core.solution.FloatSolution) → jmetal.core.solution.FloatSolution

class jmetal.core.problem.IntegerProblem(rf_path: str = None)

Bases: jmetal.core.problem.Problem

Class representing integer problems.

create_solution() → jmetal.core.solution.IntegerSolution

evaluate(solution: jmetal.core.solution.IntegerSolution) → jmetal.core.solution.IntegerSolution

class jmetal.core.problem.Problem(reference_front_path: str)

Bases: typing.Generic

Class representing problems.

MAXIMIZE = 1

MINIMIZE = -1

create_solution() → S

Creates a random solution to the problem.

Returns:Solution.

evaluate(solution: S) → S

Evaluate a solution. For any new problem inheriting from Problem, this method should be replaced.

Returns:Evaluated solution.

evaluate_constraints(solution: S)

get_name() → str

static read_front_from_file(file_path: str) → typing.List[typing.List[float]]

Reads a front from a file and returns a list.

Returns:List of solution points.

static read_front_from_file_as_solutions(file_path: str) → typing.List[S]

Reads a front from a file and returns a list of solution objects.

Returns:List of solution objects.

Solution

class jmetal.core.solution.BinarySolution(number_of_variables: int, number_of_objectives: int, number_of_constraints: int = 0)

Bases: jmetal.core.solution.Solution

Class representing float solutions

get_total_number_of_bits() → int

class jmetal.core.solution.FloatSolution(number_of_variables: int, number_of_objectives: int, number_of_constraints: int, lower_bound: typing.List[float], upper_bound: typing.List[float])

Bases: jmetal.core.solution.Solution

Class representing float solutions

class jmetal.core.solution.IntegerSolution(number_of_variables: int, number_of_objectives: int, number_of_constraints: int, lower_bound: typing.List[int], upper_bound: typing.List[int])

Bases: jmetal.core.solution.Solution

Class representing integer solutions

class jmetal.core.solution.Solution(number_of_variables: int, number_of_objectives: int, number_of_constraints: int = 0)

Bases: typing.Generic

Class representing solutions

Observable

class jmetal.core.observable.DefaultObservable

Bases: jmetal.core.observable.Observable

deregister(observer: jmetal.core.observable.Observer)

deregister_all()

notify_all(*args, **kwargs)

register(observer: jmetal.core.observable.Observer)

class jmetal.core.observable.Observable

Bases: object

deregister(observer)

deregister_all()

notify_all(*args, **kwargs)

register(observer)

class jmetal.core.observable.Observer

Bases: object

update(*args, **kwargs)

Update method

Parameters:

• args –
• kwargs –

Returns: