saealib.Population

class saealib.Population(attrs, init_capacity=100)

Bases: Generic[T_Individual]

Container for population data.

Parameters:

• attrs (list[PopulationAttribute])

• init_capacity (int)

schema

Schema defining the attributes of the population.

Type:

Dict[str, PopulationAttribute]

_data

Dictionary to store population data arrays.

Type:

Dict[str, np.ndarray]

_cache

Dictionary to store cached values (ex: nds_rank). Cleared on every value or structure modification.

Type:

Dict[str, Any]

_capacity

Current capacity of the population.

Type:

int

_size

Current size of the population.

Type:

int

_structure_version

Version number to track structure modifications.

Type:

int

_value_version

Version number to track value modifications.

Type:

int

Methods

__init__	Initialize a Population.
append	Append a new individual to the population.
argsort	Get the indices that would sort the population by a specific attribute.
clear	Clear the population.
delete	Delete individuals from the population.
empty_like	Create an empty Population with the same schema.
extend	Extend this population with another population.
extract	Extract individuals with indices, and return new Population.
get	Get the array of a specific attribute.
get_array	Get the array of a specific attribute.
get_cache	Get a cached value.
get_readonly_array	Return a read only view of the specified key.
mod_structure	Public method to call when the structure changes.
mod_value	Public method to call when the value changes.
reorder	Reorder individuals in the population.
set_cache	Set a cache value.
truncate	Cut the population to a new size.
update_array	Update array in place and bump the value version.

Method Details

Population.__init__(attrs, init_capacity=100)

Initialize a Population.

Parameters:

• attrs (List[PopulationAttribute]) – List of population attributes. Each attribute defines a column in the population.

• init_capacity (int, optional) – Initial capacity of the population, by default 100.

Return type:

None

Population.append(element=None, **kwargs)

Append a new individual to the population.

Parameters:

• element (Individual | dict | None) – Data for the additional individual

• **kwargs – Set attribute values individually and add them. Alternatively, overwrite based on the element’s value and add it.

Return type:

None

Examples

>>> pop.append(ind)
>>> pop.append({"x": x_val})
>>> pop.append(x=x_val, f=0.1)
>>> pop.append(ind, f=0.1)

Population.argsort(name, reverse=False)

Get the indices that would sort the population by a specific attribute.

Parameters:

• name (str) – The attribute name to sort by.

• reverse (bool, optional) – Whether to sort in descending order, by default False.

Return type:

ndarray

Population.clear()

Clear the population.

Return type:

None

Population.delete(index)

Delete individuals from the population.

Parameters:

index (int, slice, list[int], np.ndarray) – The index or indices of individuals to delete.

Return type:

None

Population.empty_like(capacity=None)

Create an empty Population with the same schema.

Parameters:

capacity (int) – Initial capacity of the new Population. Defaults to self._capacity.

Population.extend(other)

Extend this population with another population.

Parameters:

other (Population | dict) – The other population to extend from.

Return type:

None

Population.extract(indices)

Extract individuals with indices, and return new Population.

Parameters:

indices (np.ndarray | List[int] | slice) – Indices to extract

Return type:

Self

Population.get(key, default=None)

Get the array of a specific attribute.

Parameters:

• key (str) – The attribute name to get the array for.

• default (Any) – Returned when the key is absent.

Return type:

ndarray

Population.get_array(key)

Get the array of a specific attribute.

Parameters:

key (str) – The attribute name to get the array for.

Return type:

ndarray

Population.get_cache(key)

Get a cached value.

Returns None if the key is not found.

Parameters:

key (str) – The key of the cache.

Returns:

The cached value, or None if not found.

Return type:

Any | None

Population.get_readonly_array(key)

Return a read only view of the specified key.

Parameters:

key (str)

Return type:

ndarray

Population.mod_structure()

Public method to call when the structure changes.

Return type:

None

Population.mod_value()

Public method to call when the value changes.

Return type:

None

Population.reorder(order)

Reorder individuals in the population.

Parameters:

order (np.ndarray) – The new order of individuals.

Return type:

None

Population.set_cache(key, value)

Set a cache value.

The cache is automatically cleared when the population is modified (via mod_value or mod_structure).

Parameters:

• key (str) – The key of the cache.

• value (Any) – The value to be cached.

Return type:

None

Population.truncate(new_size)

Cut the population to a new size.

Parameters:

new_size (int) – The new size of the population.

Return type:

None

Population.update_array(key, value)

Update array in place and bump the value version.

Parameters:

• key (str)

• value (Any)

Return type:

ndarray