ribs.emitters.rankers.RankerBase¶

class ribs.emitters.rankers.RankerBase(seed: int | integer | None = None)[source]¶

Base class for rankers.

Every ranker has a rank() method that returns a list of indices that indicate how the solutions should be ranked and a reset() method that resets the internal state of the ranker (e.g. in RandomDirectionRanker).

Child classes are only required to override rank().

Methods

`rank`(emitter, archive, data, add_info)	Generates a batch of indices that represents an ordering of `data["solution"]`.
`reset`(emitter, archive)	Resets the internal state of the ranker.

abstract rank(emitter: EmitterBase, archive: ArchiveBase, data: dict[str, ndarray], add_info: dict[str, ndarray]) → tuple[ndarray, ndarray][source]¶

Generates a batch of indices that represents an ordering of data["solution"].

Parameters:¶

emitter: EmitterBase¶: Emitter that this ranker object belongs to.
archive: ArchiveBase¶: Archive used by emitter when creating and inserting solutions.
data: dict[str, ndarray]¶: Dict mapping from field names like solution and objective to arrays with data for the solutions.
add_info: dict[str, ndarray]¶: Information returned by an archive’s add() method.

Returns:¶

The first array (shape (batch_size,)) is an array of indices representing a ranking of the solutions and the second array (shape (batch_size,) or (batch_size, n_values)) is an array of values that this ranker used to rank the solutions. batch_size is the number of solutions and n_values is the number of values that the rank function used.

reset(emitter: EmitterBase, archive: ArchiveBase) → None[source]¶

Resets the internal state of the ranker.

Parameters:¶

emitter: EmitterBase¶: Emitter that this ranker object belongs to.
archive: ArchiveBase¶: Archive used by emitter when creating and inserting solutions.