callback_async {bbotk}

Create Asynchronous Optimization Callback

Description

Function to create a CallbackAsync.

Optimization callbacks can be called from different stages of optimization process. The stages are prefixed with ⁠on_*⁠.

Start Optimization
     - on_optimization_begin
    Start Worker
         - on_worker_begin
         - on_worker_end
    End Worker
     - on_result
     - on_optimization_end
End Optimization

See also the section on parameters for more information on the stages. A optimization callback works with ContextAsync.

Usage

callback_async(
  id,
  label = NA_character_,
  man = NA_character_,
  on_optimization_begin = NULL,
  on_worker_begin = NULL,
  on_worker_end = NULL,
  on_result = NULL,
  on_optimization_end = NULL
)

Arguments

id

(character(1))
Identifier for the new instance.

label

(character(1))
Label for the new instance.

man

(character(1))
String in the format ⁠[pkg]::[topic]⁠ pointing to a manual page for this object. The referenced help package can be opened via method ⁠$help()⁠.

on_optimization_begin

(⁠function()⁠)
Stage called at the beginning of the optimization in the main process. Called in Optimizer$optimize(). The functions must have two arguments named callback and context.

on_worker_begin

(⁠function()⁠)
Stage called at the beginning of the optimization on the worker. Called in the worker loop. The functions must have two arguments named callback and context.

on_worker_end

(⁠function()⁠)
Stage called at the end of the optimization on the worker. Called in the worker loop. The functions must have two arguments named callback and context.

on_result

(⁠function()⁠)
Stage called after result are written. Called in OptimInstance$assign_result(). The functions must have two arguments named callback and context.

on_optimization_end

(⁠function()⁠)
Stage called at the end of the optimization in the main process. Called in Optimizer$optimize(). The functions must have two arguments named callback and context.

Details

A callback can write data to its state (⁠$state⁠), e.g. settings that affect the callback itself. The ContextAsync allows to modify the instance, archive, optimizer and final result.