Skip to contents

A paradox::ParamSet defining the codomain of a function. The parameter set must contain at least one target parameter tagged with "minimize" or "maximize". The codomain may contain extra parameters which are ignored when calling the Archive methods $best(), $nds_selection() and $cols_y. This class is usually constructed internally from a paradox::ParamSet when Objective is initialized.

Super class

paradox::ParamSet -> Codomain

Active bindings

is_target

(named logical())
Position is TRUE for target parameters.

target_length

(integer())
Returns number of target parameters.

target_ids

(character())
IDs of contained target parameters.

target_tags

(named list() of character())
Tags of target parameters.

maximization_to_minimization

(integer())
Returns a numeric vector with values -1 and 1. Multiply with the outcome of a maximization problem to turn it into a minimization problem.

direction

(integer())
Returns 1 for minimization and -1 for maximization. If the codomain contains multiple parameters an integer vector is returned. Multiply with the outcome of a maximization problem to turn it into a minimization problem.

Examples


# define objective function
fun = function(xs) {
  c(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"),
  time = p_dbl()
)

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