pg.evolution.Pipeline¶

Accessible via pg.evolution.Pipeline.

class Pipeline(ops)[source]¶

Chaining operations into a pipeline.

A pipeline operation chains multiple operations by passing the output of previous operation to the next operations.

Example:

pg.evolution.Pipeline([
  pg.evolution.selectors.Random(10)
  pg.evolution.selectors.Top(1),
  pg.evolution.mutators.Uniform()
])

which is equivalent to:

(pg.evolution.selectors.Random(10)
  >> pg.evolution.selectors.Top(1)
  >> pg.evolution.mutators.Uniform())

The code above returns a uniformly mutated DNA from the winner of 10 randomly selected DNA from the input.

Methods:

call(inputs, global_state[, step])

Subclasses should override this method.

call(inputs, global_state, step=0)[source]¶

Subclasses should override this method.

The global_state and step are optional for the subclasses’ call signature.

Return type:

List[Any]

Parameters:

inputs – A list of values as inputs.
global_state – An AttributeDict object as the global state container, which is readable/writable during the operation.
step – Number of examples historically proposed, which can be used for determining a cross over schedule.

Returns:

A list of values as output of current operation.