R: Optimization Instance with budget and archive

OptimInstanceMultiCrit {bbotk} | R Documentation

## Optimization Instance with budget and archive

### Description

Wraps a multi-criteria Objective function with extra services for convenient evaluation. Inherits from OptimInstance.

- Automatic storing of results in an Archive after evaluation.

- Automatic checking for termination. Evaluations of design points are performed in batches. Before a batch is evaluated, the Terminator is queried for the remaining budget. If the available budget is exhausted, an exception is raised, and no further evaluations can be performed from this point on.

### Super class

`bbotk::OptimInstance` -> `OptimInstanceMultiCrit`

### Active bindings

`result_x_domain`

  (`list()`)
  (transformed) x part of the result in the domain space of the objective.

`result_y`

  (`numeric(1)`)
  Optimal outcome.

### Methods

#### Public methods

- `OptimInstanceMultiCrit$new()`

- `OptimInstanceMultiCrit$assign_result()`

- `OptimInstanceMultiCrit$clone()`

Inherited methods

- `bbotk::OptimInstance$clear()`

- `bbotk::OptimInstance$eval_batch()`

- `bbotk::OptimInstance$format()`

- `bbotk::OptimInstance$objective_function()`

- `bbotk::OptimInstance$print()`

#### Method `new()`

Creates a new instance of this R6 class.

##### Usage

    OptimInstanceMultiCrit$new(
      objective,
      search_space = NULL,
      terminator,
      keep_evals = "all",
      check_values = TRUE
    )

##### Arguments

`objective`

  (Objective).

`search_space`

  (paradox::ParamSet)
  Specifies the search space for the Optimizer. The paradox::ParamSet describes either a subset of the `domain` of the Objective or it describes a set of parameters together with a `trafo` function that transforms values from the search space to values of the domain. Depending on the context, this value defaults to the domain of the objective.

`terminator`

  (Terminator)
  Multi-criteria terminator.

`keep_evals`

  (`character(1)`)
  Keep `all` or only `best` evaluations in archive?

`check_values`

  (`logical(1)`)
  Should x-values that are added to the archive be checked for validity? Search space that is logged into archive.

#### Method `assign_result()`

The Optimizer object writes the best found points and estimated performance values here (probably the Pareto set / front). For internal use.

##### Usage

    OptimInstanceMultiCrit$assign_result(xdt, ydt)

##### Arguments

`xdt`

  (`data.table::data.table()`)
  Set of untransformed points / points from the search space. One point per row, e.g. `data.table(x1 = c(1, 3), x2 = c(2, 4))`. Column names have to match ids of the `search_space`. However, `xdt` can contain additional columns.

`ydt`

  (`numeric(1)`)
  Optimal outcomes, e.g. the Pareto front.

#### Method `clone()`

The objects of this class are cloneable with this method.

##### Usage

    OptimInstanceMultiCrit$clone(deep = FALSE)

##### Arguments

`deep`

  Whether to make a deep clone.

[Package bbotk version 0.3.1 Index]