bbotk (version 0.2.2)

Terminator: Abstract Terminator Class

Description

Abstract Terminator class that implements the base functionality each terminator must provide. A terminator is an object that determines when to stop the optimization.

Termination of optimization works as follows:

  • Evaluations in a instance are performed in batches.

  • Before each batch evaluation, the Terminator is checked, and if it is positive, we stop.

  • The optimization algorithm itself might decide not to produce any more points, or even might decide to do a smaller batch in its last evaluation.

Therefore the following note seems in order: While it is definitely possible to execute a fine-grained control for termination, and for many optimization algorithms we can specify exactly when to stop, it might happen that too few or even too many evaluations are performed, especially if multiple points are evaluated in a single batch (c.f. batch size parameter of many optimization algorithms). So it is advised to check the size of the returned archive, in particular if you are benchmarking multiple optimization algorithms.

Arguments

Public fields

param_set

paradox::ParamSet Set of control parameters for terminator.

properties

character() Set of properties.

Methods

Public methods

Method new()

Creates a new instance of this R6 class.

Usage

Terminator$new(param_set = ParamSet$new(), properties = character())

Arguments

param_set

(paradox::ParamSet) Set of control parameters for terminator.

properties

(character()) Set of properties.

Method format()

Helper for print outputs.

Usage

Terminator$format()

Method print()

Printer.

Usage

Terminator$print(...)

Arguments

...

(ignored).

Method clone()

The objects of this class are cloneable with this method.

Usage

Terminator$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

See Also

Other Terminator: mlr_terminators_clock_time, mlr_terminators_combo, mlr_terminators_evals, mlr_terminators_none, mlr_terminators_perf_reached, mlr_terminators_run_time, mlr_terminators_stagnation_batch, mlr_terminators_stagnation, mlr_terminators