CallbackAsync: Create Asynchronous Optimization Callback

In bbotk: Black-Box Optimization Toolkit

Create Asynchronous Optimization Callback

Description

Specialized mlr3misc::Callback for asynchronous optimization. Callbacks allow to customize the behavior of processes in bbotk. The callback_async() function creates a CallbackAsync. Predefined callbacks are stored in the dictionary mlr_callbacks and can be retrieved with clbk(). For more information on optimization callbacks see callback_async().

Super class

mlr3misc::Callback -> CallbackAsync

Public fields

on_optimization_begin

(⁠function()⁠)
Stage called at the beginning of the optimization in the main process. Called in Optimizer$optimize().

on_worker_begin

(⁠function()⁠)
Stage called at the beginning of the optimization on the worker. Called in the worker loop.

on_optimizer_before_eval

(⁠function()⁠)
Stage called after the optimizer proposes points. Called in OptimInstance$.eval_point().

on_optimizer_after_eval

(⁠function()⁠)
Stage called after points are evaluated. Called in OptimInstance$.eval_point().

on_worker_end

(⁠function()⁠)
Stage called at the end of the optimization on the worker. Called in the worker loop.

on_result_begin

(⁠function()⁠)
Stage called before the results are written. Called in OptimInstance$assign_result().

on_result_end

(⁠function()⁠)
Stage called after the results are written. Called in OptimInstance$assign_result().

on_optimization_end

(⁠function()⁠)
Stage called at the end of the optimization in the main process. Called in Optimizer$optimize().

Methods

Public methods

• CallbackAsync$clone()

Inherited methods

• mlr3misc::Callback$call()
• mlr3misc::Callback$format()
• mlr3misc::Callback$help()
• mlr3misc::Callback$initialize()
• mlr3misc::Callback$print()

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Method clone()

The objects of this class are cloneable with this method.

Usage

CallbackAsync$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

See Also

callback_async()

bbotk documentation built on Nov. 5, 2025, 6:23 p.m.