Local Search

Implements a simple Local Search, see local_search() for details. Currently, setting initial points is not supported.

Dictionary

This Optimizer can be instantiated via the dictionary mlr_optimizers or with the associated sugar function opt():

mlr_optimizers$get("local_search")
opt("local_search")

Parameters

The same as for local_search_control(), with the same defaults (except for minimize).

Progress Bars

$optimize() supports progress bars via the package progressr combined with a Terminator. Simply wrap the function in progressr::with_progress() to enable them. We recommend to use package progress as backend; enable with progressr::handlers("progress").

Super classes

bbotk::Optimizer -> bbotk::OptimizerBatch -> OptimizerBatchLocalSearch

Methods

Public methods

• OptimizerBatchLocalSearch$new()

• OptimizerBatchLocalSearch$clone()

Inherited methods

• bbotk::Optimizer$format()
• bbotk::Optimizer$help()
• bbotk::Optimizer$print()
• bbotk::OptimizerBatch$optimize()

---

Method new()

Creates a new instance of this R6 class.

Usage

OptimizerBatchLocalSearch$new()

---

Method clone()

The objects of this class are cloneable with this method.

Usage

OptimizerBatchLocalSearch$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Examples

# define the objective function
fun = function(xs) {
  list(y = - (xs[[1]] - 2)^2 - (xs[[2]] + 3)^2 + 10)
}

# set domain
domain = ps(
  x1 = p_dbl(-10, 10),
  x2 = p_dbl(-5, 5)
)

# set codomain
codomain = ps(
  y = p_dbl(tags = "maximize")
)

# create objective
objective = ObjectiveRFun$new(
  fun = fun,
  domain = domain,
  codomain = codomain,
  properties = "deterministic"
)

# initialize instance
instance = oi(
  objective = objective,
  terminator = trm("evals", n_evals = 20)
)

# load optimizer
optimizer = opt("local_search")

# trigger optimization
optimizer$optimize(instance)
#>          x1        x2  x_domain        y
#>       <num>     <num>    <list>    <num>
#> 1: 2.652858 -2.625208 <list[2]> 9.433308

# all evaluated configurations
instance$archive
#> 
#> ── <ArchiveBatch> - Data Table Storage ─────────────────────────────────────────
#>         x1    x2     y           timestamp batch_nr x_domain_x1 x_domain_x2
#>      <num> <num> <num>              <POSc>    <int>       <num>       <num>
#>   1:   3.2  -0.9     4 2026-02-18 13:47:38        1         3.2        -0.9
#>   2:   0.7  -4.8     5 2026-02-18 13:47:38        1         0.7        -4.8
#>   3:   9.6   4.0   -97 2026-02-18 13:47:38        1         9.6         4.0
#>   4:   1.0  -2.6     9 2026-02-18 13:47:38        1         1.0        -2.6
#>   5:  -7.2   1.2   -93 2026-02-18 13:47:38        1        -7.2         1.2
#>  ---                                                                       
#> 106:  -2.9   5.0   -78 2026-02-18 13:47:39        2        -2.9         5.0
#> 107:  -2.9   4.7   -73 2026-02-18 13:47:39        2        -2.9         4.7
#> 108:  -4.4   3.8   -77 2026-02-18 13:47:39        2        -4.4         3.8
#> 109:  -5.5   3.8   -92 2026-02-18 13:47:39        2        -5.5         3.8
#> 110:  -2.9   2.6   -45 2026-02-18 13:47:39        2        -2.9         2.6

# best performing configuration
instance$result
#>          x1        x2  x_domain        y
#>       <num>     <num>    <list>    <num>
#> 1: 2.652858 -2.625208 <list[2]> 9.433308