culebra.trainer.ea.HomogeneousParallelIslandsEA class¶
- class HomogeneousParallelIslandsEA(solution_cls: type[Individual], species: Species, fitness_function: FitnessFunction, subtrainer_cls: type[SinglePopEA], max_num_iters: int | None = None, custom_termination_func: Callable[[HomogeneousParallelIslandsEA], bool] | None = None, pop_size: int | None = None, crossover_func: Callable[[Individual, Individual], tuple[Individual, Individual]] | None = None, mutation_func: Callable[[Individual, float], tuple[Individual]] | None = None, selection_func: Callable[[list[Individual], int, Any], list[Individual]] | None = None, crossover_prob: float | None = None, mutation_prob: float | None = None, gene_ind_mutation_prob: float | None = None, selection_func_params: dict[str, Any] | None = None, num_subtrainers: int | None = None, representation_size: int | None = None, representation_freq: int | None = None, representation_topology_func: Callable[[int, int, Any], list[int]] | None = None, representation_topology_func_params: dict[str, Any] | None = None, representation_selection_func: Callable[[list[Individual], Any], Individual] | None = None, representation_selection_func_params: dict[str, Any] | None = None, checkpoint_activation: bool | None = None, checkpoint_freq: int | None = None, checkpoint_filename: str | None = None, verbosity: bool | None = None, random_seed: int | None = None, **subtrainer_params: Any)¶
Bases:
HomogeneousIslandsEA,ParallelDistributedTrainer.
Class attributes¶
- HomogeneousParallelIslandsEA.objective_stats = {'Avg': <function mean>, 'Max': <function max>, 'Min': <function min>, 'Std': <function std>}¶
Statistics calculated for each objective.
- HomogeneousParallelIslandsEA.stats_names = ('Iter', 'Pop', 'NEvals')¶
Statistics calculated each iteration.
Class methods¶
- classmethod HomogeneousParallelIslandsEA.load(filename: str) Base¶
Load a serialized object from a file.
- Parameters:
filename (str) – The file name.
- Returns:
The loaded object
- Raises:
TypeError – If filename is not a valid file name
ValueError – If the filename extension is not
SERIALIZED_FILE_EXTENSION
Properties¶
- property HomogeneousParallelIslandsEA.checkpoint_filename: str¶
Checkpoint file path.
- Return type:
- Setter:
Modify the checkpoint file path
- Parameters:
value (str) – New value for the checkpoint file path. If set to
None,_default_checkpoint_filenameis chosen- Raises:
TypeError – If value is not a valid file name
ValueError – If the value extension is not
SERIALIZED_FILE_EXTENSION
- property HomogeneousParallelIslandsEA.checkpoint_freq: int¶
Checkpoint frequency.
- Return type:
- Setter:
Modify the checkpoint frequency
- Parameters:
value (int) – New value for the checkpoint frequency. If set to
None,_default_checkpoint_freqis chosen- Raises:
TypeError – If value is not an integer
ValueError – If value is not a positive number
- property HomogeneousParallelIslandsEA.container: Trainer | None¶
Container of this trainer.
The trainer container is only used by distributed trainers. For the rest of trainers defaults to
None.
- property HomogeneousParallelIslandsEA.crossover_func: Callable[[Individual, Individual], tuple[Individual, Individual]]¶
Crossover function.
- Returns:
If subtrainers have been generated, the subtrainers crossover function. Otherwise, the crossover function value used to call the constructor
- Return type:
- Setter:
Set a new crossover function
- Parameters:
func (Callable) – The new crossover function. If omitted,
_default_crossover_funcis chosen- Raises:
TypeError – If func is not callable
- property HomogeneousParallelIslandsEA.crossover_prob: float¶
Crossover probability.
- Returns:
If subtrainers have been generated, the subtrainers crossover probability. Otherwise, the crossover probability value used to call the constructor
- Return type:
- Setter:
Set a new crossover probability
- Parameters:
prob (float) – The new probability. If omitted,
_default_crossover_probis chosen- Raises:
TypeError – If prob is not a real number
ValueError – If prob is not in (0, 1)
- property HomogeneousParallelIslandsEA.custom_termination_func: Callable[[Trainer], bool] | None¶
Custom termination criterion.
Although the trainer will always stop when the
max_num_itersare reached, a custom termination criterion can be set to detect convergente and stop the trainer earlier. This custom termination criterion must be a function which receives the trainer as its unique argument and returns a boolean value,Trueif the search should terminate orFalseotherwise.If more than one arguments are needed to define the termination condition,
functools.partial()can be used:from functools import partial def my_crit(trainer, max_iters): if trainer.current_iter < max_iters: return False return True trainer.custom_termination_func = partial(my_crit, max_iters=10)
- property HomogeneousParallelIslandsEA.fitness_function: FitnessFunction¶
Training fitness function.
- Return type:
- Setter:
Set a new fitness function
- Parameters:
func (FitnessFunction) – The new training fitness function
- Raises:
TypeError – If func is not a valid fitness function
- property HomogeneousParallelIslandsEA.gene_ind_mutation_prob: float¶
Gene independent mutation probability.
- Returns:
If subtrainers have been generated, the subtrainers gene independent mutation probability. Otherwise, the gene independent mutation probability value used to call the constructor
- Return type:
- Setter:
Set a new gene independent mutation probability
- Parameters:
prob (float) – The new probability. If omitted,
_default_gene_ind_mutation_probis chosen- Raises:
TypeError – If prob is not a real number
ValueError – If prob is not in (0, 1)
- property HomogeneousParallelIslandsEA.index: int¶
Trainer index.
The trainer index is only used by distributed trainers. For the rest of trainers
_default_indexis used.- Return type:
- Setter:
Set a new value for trainer index.
- Parameters:
value (int) – New value for the trainer index. If set to
None,_default_indexis chosen- Raises:
TypeError – If value is not an integer
ValueError – If value is a negative number
- property HomogeneousParallelIslandsEA.max_num_iters: int¶
Maximum number of iterations.
- Return type:
- Setter:
Set a new value for the maximum number of iterations
- Parameters:
value (int) – The new maximum number of iterations. If set to
None, the default maximum number of iterations,_default_max_num_iters, is chosen- Raises:
TypeError – If value is not an integer
ValueError – If value is not a positive number
- property HomogeneousParallelIslandsEA.mutation_func: Callable[[Individual, float], tuple[Individual]]¶
Mutation function.
- Returns:
If subtrainers have been generated, the subtrainers mutation function. Otherwise, the mutation function value used to call the constructor
- Return type:
- Setter:
Set a new mutation function
- Parameters:
func (Callable) – The new mutation function. If omitted,
_default_mutation_funcis chosen- Raises:
TypeError – If func is not callable
- property HomogeneousParallelIslandsEA.mutation_prob: float¶
Mutation probability.
- Returns:
If subtrainers have been generated, the subtrainers mutation probability. Otherwise, the mutation probability value used to call the constructor
- Return type:
- Setter:
Set a new mutation probability
- Parameters:
prob (float) – The new probability. If omitted,
_default_mutation_probis chosen- Raises:
TypeError – If prob is not a real number
ValueError – If prob is not in (0, 1)
- property HomogeneousParallelIslandsEA.num_evals: int | None¶
Number of evaluations performed while training.
- property HomogeneousParallelIslandsEA.num_subtrainers: int¶
Number of subtrainers.
- Return type:
- Setter:
Set a new value for the number of subtrainers
- Parameters:
value (int) – The new number of subtrainers. If set to
None,_default_num_subtrainersis chosen- Raises:
TypeError – If value is not an integer
ValueError – If value is not a positive number
- property HomogeneousParallelIslandsEA.pop_size: int¶
Population size.
- Returns:
If subtrainers have been generated, the subtrainers population size. Otherwise, the population size value used to call the constructor
- Return type:
- Setter:
Set a new population size
- Parameters:
size (int) – The new population size. If omitted,
_default_pop_sizeis chosen- Raises:
ValueError – If size is not greater than zero
- property HomogeneousParallelIslandsEA.representation_freq: int¶
Number of iterations between representatives sendings.
- Return type:
- Setter:
Set a new value for the frequency
- Parameters:
value (int) – The new frequency. If set to
None,_default_representation_freqis chosen- Raises:
TypeError – If value is not an integer
ValueError – If value is not a positive number
- property HomogeneousParallelIslandsEA.representation_selection_func: Callable[[list[Solution], Any], Solution]¶
Representation selection policy function.
- Returns:
A function that chooses which solutions are selected as representatives of each subtrainer
- Return type:
- Setter:
Set new representation selection policy function.
- Parameters:
func (Callable) – The new function. If set to
None,_default_representation_selection_funcis chosen- Raises:
TypeError – If func is not callable
- property HomogeneousParallelIslandsEA.representation_selection_func_params: dict[str, Any]¶
Parameters of the representation selection function.
- property HomogeneousParallelIslandsEA.representation_size: int¶
Representation size.
- Returns:
The number of representatives sent to the other subtrainers
- Return type:
- Setter:
Set a new representation size
- Parameters:
size (int) – The new size. If set to
None,_default_representation_sizeis chosen- Raises:
TypeError – If size is not an integer number
ValueError – If size is not positive
- property HomogeneousParallelIslandsEA.representation_topology_func: Callable[[int, int, Any], list[int]]¶
Representation topology function.
- Return type:
- Setter:
Set new representation topology function
- Parameters:
func (Callable) – The new function. If set to
None,_default_representation_topology_funcis chosen- Raises:
TypeError – If func is not callable
- property HomogeneousParallelIslandsEA.representation_topology_func_params: dict[str, Any]¶
Parameters of the representation topology function.
- property HomogeneousParallelIslandsEA.representatives: list[list[Solution | None]] | None¶
Representatives of the other species.
Only used by cooperative trainers. If the trainer does not use representatives,
Noneis returned.
- property HomogeneousParallelIslandsEA.selection_func: Callable[[list[Individual], int, Any], list[Individual]]¶
Selection function.
- Returns:
If subtrainers have been generated, the subtrainers selection function. Otherwise, the selection function value used to call the constructor
- Return type:
- Setter:
Set a new selection function
- Parameters:
func (Callable) – The new selection function. If omitted,
_default_selection_funcis chosen- Raises:
TypeError – If func is not callable
- property HomogeneousParallelIslandsEA.selection_func_params: dict[str, Any]¶
Parameters of the selection function.
- Returns:
If subtrainers have been generated, the subtrainers parameters for the selection function. Otherwise, the parameters for the selection function used to call the constructor
- Return type:
- Setter:
Set new parameters for the selection function
- Parameters:
params – The new parameters. If omitted,
_default_selection_func_paramsis chosen- Raises:
- property HomogeneousParallelIslandsEA.subtrainer_checkpoint_filenames: Generator[str, None, None]¶
Checkpoint file name for all the subtrainers.
- property HomogeneousParallelIslandsEA.subtrainer_cls: type[SingleSpeciesTrainer]¶
Trainer class to handle the subtrainers.
Each subtrainer will be handled by a single-species trainer.
- Return type:
- Setter:
Set a new trainer class to handle the subtrainers
- Parameters:
cls (type[SingleSpeciesTrainer]) – The new class
- Raises:
TypeError – If cls is not a valid trainer class
- property HomogeneousParallelIslandsEA.subtrainer_params: dict[str, Any]¶
Custom parameters for the subtrainers.
- property HomogeneousParallelIslandsEA.subtrainers: list[SingleSpeciesTrainer] | None¶
Subtrainers.
One single-species trainer for each subtrainer.
- Return type:
Private properties¶
- property HomogeneousParallelIslandsEA._default_checkpoint_activation: bool¶
Default checkpointing activation.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_checkpoint_filename: str¶
Default checkpointing file name.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_checkpoint_freq: int¶
Default checkpointing frequency.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_crossover_func: Callable[[Individual, Individual], tuple[Individual, Individual]]¶
Default crossover function.
- property HomogeneousParallelIslandsEA._default_crossover_prob: float¶
Default crossover probability.
- property HomogeneousParallelIslandsEA._default_gene_ind_mutation_prob: float¶
Default gene independent mutation probability.
- property HomogeneousParallelIslandsEA._default_max_num_iters: int¶
Default maximum number of iterations.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_mutation_func: Callable[[Individual, float], tuple[Individual]]¶
Default mutation function.
- property HomogeneousParallelIslandsEA._default_num_subtrainers: int¶
Default number of subtrainers.
- Returns:
The number of CPU cores
- Return type:
- property HomogeneousParallelIslandsEA._default_representation_freq: int¶
Default number of iterations between representatives sending.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_representation_selection_func: Callable[[list[Solution], Any], Solution]¶
Default selection policy function to choose the representatives.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_representation_selection_func_params: dict[str, Any]¶
Default parameters for the representatives selection policy function.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_representation_size: int¶
Default number of representatives sent to the other subtrainers.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_representation_topology_func: Callable[[int, int, Any], list[int]]¶
Default topology function.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_representation_topology_func_params: dict[str, Any]¶
Default parameters for the default topology function.
- Returns:
- Return type:
- property HomogeneousParallelIslandsEA._default_selection_func: Callable[[list[Individual], int, Any], list[Individual]]¶
Default selection function.
- property HomogeneousParallelIslandsEA._default_selection_func_params: dict[str, Any]¶
Parameters of the default selection function.
Static methods¶
- static HomogeneousParallelIslandsEA.receive_representatives(subtrainer: SinglePopEA) None¶
Receive representative solutions.
- Parameters:
subtrainer (SinglePopEA) – The subtrainer receiving representatives
- static HomogeneousParallelIslandsEA.send_representatives(subtrainer: SinglePopEA) None¶
Send representatives.
- Parameters:
subtrainer (SinglePopEA) – The sender subtrainer
Methods¶
- HomogeneousParallelIslandsEA.best_representatives() list[list[Solution]] | None¶
Return a list of representatives from each species.
Only used for cooperative trainers.
- HomogeneousParallelIslandsEA.best_solutions() tuple[HallOfFame]¶
Get the best solutions found for each species.
- Returns:
One Hall of Fame for each species
- Return type:
- HomogeneousParallelIslandsEA.dump(filename: str) None¶
Serialize this object and save it to a file.
- Parameters:
filename (str) – The file name.
- Raises:
TypeError – If filename is not a valid file name
ValueError – If the filename extension is not
SERIALIZED_FILE_EXTENSION
- HomogeneousParallelIslandsEA.evaluate(sol: Solution, fitness_func: FitnessFunction | None = None, index: int | None = None, representatives: Sequence[Sequence[Solution | None]] | None = None) None¶
Evaluate one solution.
Its fitness will be modified according with the fitness function results. Besides, if called during training, the number of evaluations will be also updated.
- Parameters:
sol (Solution) – The solution
fitness_func (FitnessFunction) – The fitness function. If omitted, the default training fitness function (
fitness_function) is usedindex (int) – Index where sol should be inserted in the representatives sequence to form a complete solution for the problem. If omitted,
indexis usedrepresentatives (Sequence[Sequence[Solution]]) – Sequence of representatives of other species or
None(if no representatives are needed to evaluate sol). If omitted, the current value ofrepresentativesis used
- HomogeneousParallelIslandsEA.reset() None¶
Reset the trainer.
Delete the state of the trainer (with
_reset_state()) and also all the internal data structures needed to perform the search (with_reset_internals()).This method should be invoqued each time a hyper parameter is modified.
- HomogeneousParallelIslandsEA.test(best_found: Sequence[HallOfFame], fitness_func: FitnessFunction | None = None, representatives: Sequence[Sequence[Solution]] | None = None) None¶
Apply the test fitness function to the solutions found.
Update the solutions in best_found with their test fitness.
- Parameters:
best_found (Sequence[HallOfFame]) – The best solutions found for each species. One
HallOfFamefor each speciesfitness_func (FitnessFunction) – Fitness function used to evaluate the final solutions. If ommited, the default training fitness function (
fitness_function) will be usedrepresentatives (Sequence[Sequence[Solution]]) – Sequence of representatives of other species or
None(if no representatives are needed). If omitted, the current value ofrepresentativesis used
- Raises:
TypeError – If any parameter has a wrong type
ValueError – If any parameter has an invalid value.
- HomogeneousParallelIslandsEA.train(state_proxy: DictProxy | None = None) None¶
Perform the training process.
- Parameters:
state_proxy (DictProxy) – dictionary proxy to copy the output state of the trainer procedure. Only used if train is executed within a
multiprocess.Process. Defaults toNone
Private methods¶
- HomogeneousParallelIslandsEA._default_termination_func() bool¶
Default termination criterion.
- Returns:
Trueifmax_num_itersiterations have been run- Return type:
- abstract HomogeneousParallelIslandsEA._do_iteration() None¶
Implement an iteration of the search process.
This abstract method should be implemented by subclasses in order to implement the desired behavior.
- HomogeneousParallelIslandsEA._do_iteration_stats() None¶
Perform the iteration stats.
This method should be implemented by subclasses in order to perform the adequate stats.
- HomogeneousParallelIslandsEA._finish_iteration() None¶
Finish an iteration.
Finish the iteration metrics (number of evaluations, execution time) after each iteration is run.
- HomogeneousParallelIslandsEA._finish_search() None¶
Finish the search process.
This method is called after the search has finished. It can be overridden to perform any treatment of the solutions found.
- HomogeneousParallelIslandsEA._generate_subtrainers() None¶
Generate the subpopulation trainers.
Also assign an
indexand acontainerto eachSinglePopEAsubtrainer, and change the subpopulation subtrainers’checkpoint_filenameaccording to the container checkpointing file name and each subpopulation index.Finally, the
_preprocess_iteration()and_postprocess_iteration()methods of thesubtrainer_clsclass are dynamically overridden, in order to allow individuals exchange between subtrainers, if necessary.
- HomogeneousParallelIslandsEA._get_state() dict[str, Any]¶
Return the state of this trainer.
Default state is a dictionary composed of the values of the
logbook,num_evals,runtime,current_iter, andrepresentativestrainer properties, along with a private boolean attribute that informs if the search has finished and also the states of therandomandnumpy.randommodules.If subclasses use any more properties to keep their state, the
_get_state()and_set_state()methods must be overridden to take into account such properties.- Return type:
- HomogeneousParallelIslandsEA._init_internals() None¶
Set up the trainer internal data structures to start searching.
Overridden to create a multiprocess manager and proxies to communicate with the processes running the subtrainers.
- HomogeneousParallelIslandsEA._init_representatives() None¶
Init the representatives of the other species.
Only used for cooperative approaches, which need representatives of all the species to form a complete solution for the problem. Cooperative subclasses of the
Trainerclass should override this method to get the representatives of the other species initialized.
- HomogeneousParallelIslandsEA._init_search() None¶
Init the search process.
Initialize the state of the trainer (with
_init_state()) and all the internal data structures needed (with_init_internals()) to perform the search.
- HomogeneousParallelIslandsEA._init_state() None¶
Init the trainer state.
If there is any checkpoint file, the state is initialized from it with the
_load_state()method. Otherwise a new initial state is generated with the_new_state()method.
- HomogeneousParallelIslandsEA._load_state() None¶
Load the state of the last checkpoint.
- Raises:
Exception – If the checkpoint file can’t be loaded
- HomogeneousParallelIslandsEA._new_state() None¶
Generate a new trainer state.
Overridden to set the overall runtime and number of evaluations to
None, since their final values will be generated from the subtrainers’ state, once the trainer has finished.
- HomogeneousParallelIslandsEA._postprocess_iteration() None¶
Postprocess after doing the iteration.
Subclasses should override this method to make any postprocessment after performing an iteration.
- HomogeneousParallelIslandsEA._preprocess_iteration() None¶
Preprocess before doing the iteration.
Subclasses should override this method to make any preprocessment before performing an iteration.
- HomogeneousParallelIslandsEA._reset_internals() None¶
Reset the internal structures of the trainer.
Overridden to reset the multiprocess manager and proxies.
- HomogeneousParallelIslandsEA._reset_state() None¶
Reset the trainer state.
If subclasses overwrite the
_new_state()method to add any new property to keep their state, this method should also be overridden to reset the full state of the trainer.
- HomogeneousParallelIslandsEA._save_state() None¶
Save the state at a new checkpoint.
- Raises:
Exception – If the checkpoint file can’t be written
- HomogeneousParallelIslandsEA._search() None¶
Apply the search algorithm.
Each subtrainer runs in a different process.
- HomogeneousParallelIslandsEA._set_cooperative_fitness(sol: Solution, fitness_trials_values: [Sequence[tuple[float]]]) None¶
Estimate a solution fitness from multiple evaluation trials.
Applies an average of the fitness trials values. Trainers requiring another estimation should override this method.
- HomogeneousParallelIslandsEA._set_state(state: dict[str, Any]) None¶
Set the state of this trainer.
If subclasses use any more properties to keep their state, the
_get_state()and_set_state()methods must be overridden to take into account such properties.- Parameters:
state (dict) – The last loaded state
- HomogeneousParallelIslandsEA._start_iteration() None¶
Start an iteration.
Prepare the iteration metrics (number of evaluations, execution time) before each iteration is run.
- HomogeneousParallelIslandsEA._termination_criterion() bool¶
Control the search termination.
- Returns:
Trueif either the default termination criterion or a custom termination criterion is met. The default termination criterion is implemented by the_default_termination_func()method. Another custom termination criterion can be set withcustom_termination_funcmethod.- Return type:

