Returns the gap between the current best and the known optimum. Assumes minimization; for maximization, negate both values.
Arguments
- archive
(bbotk::ArchiveBatch) The archive.
- surrogate
(mlr3mbo::Surrogate) Ignored.
- optimum
(
numeric(1)) The known optimal value.- target
(
character(1)) Target column name.- ...
Ignored.