R: Optimization Instance with budget and archive

OptimInstanceSingleCrit {bbotk} | R Documentation

## Optimization Instance with budget and archive

### Description

Wraps a single-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` -> `OptimInstanceSingleCrit`

### Methods

#### Public methods

- `OptimInstanceSingleCrit$new()`

- `OptimInstanceSingleCrit$assign_result()`

- `OptimInstanceSingleCrit$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

    OptimInstanceSingleCrit$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).

`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 point and estimated performance value here. For internal use.

##### Usage

    OptimInstanceSingleCrit$assign_result(xdt, y)

##### 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.

`y`

  (`numeric(1)`)
  Optimal outcome.

#### Method `clone()`

The objects of this class are cloneable with this method.

##### Usage

    OptimInstanceSingleCrit$clone(deep = FALSE)

##### Arguments

`deep`

  Whether to make a deep clone.

[Package bbotk version 0.5.3 Index]