Class GramacyLee2012

java.lang.Object
org.cicirello.search.problems.GramacyLee2012
All Implemented Interfaces:
Splittable<Initializer<SingleReal>>, Initializer<SingleReal>, OptimizationProblem<SingleReal>, Problem<SingleReal>

public final class GramacyLee2012 extends Object implements OptimizationProblem<SingleReal>, Initializer<SingleReal>

A continuous function with a large number of local minimums, and a single global minimum, defined for input x in [0.5, 2.5].

This minimization problem was introduced in:

  • Gramacy, R.B.; Lee, H.K.H. Cases for the nugget in modeling computer experiments. Statistics and Computing 2012, 22, 713–722. doi:10.1007/s11222-010-9224-x.
  • Constructor Details

    • GramacyLee2012

      public GramacyLee2012()
      Constructs the GramacyLee2012 cost function.
  • Method Details

    • cost

      public double cost(SingleReal candidate)
      Description copied from interface: OptimizationProblem
      Computes the cost of a candidate solution to the problem instance. The lower the cost, the more optimal the candidate solution.
      Specified by:
      cost in interface OptimizationProblem<SingleReal>
      Parameters:
      candidate - The candidate solution to evaluate.
      Returns:
      The cost of the candidate solution. Lower cost means better solution.
    • value

      public double value(SingleReal candidate)
      Description copied from interface: OptimizationProblem
      Computes the value of the candidate solution within the usual constraints and interpretation of the problem.
      Specified by:
      value in interface OptimizationProblem<SingleReal>
      Parameters:
      candidate - The candidate solution to evaluate.
      Returns:
      The actual optimization value of the candidate solution.
    • createCandidateSolution

      public SingleReal createCandidateSolution()
      Description copied from interface: Initializer
      Creates one candidate solution to a problem.
      Specified by:
      createCandidateSolution in interface Initializer<SingleReal>
      Returns:
      a candidate solution to a problem instance.
    • split

      public GramacyLee2012 split()
      Description copied from interface: Splittable
      Generates a functionally identical copy of this object, for use in multithreaded implementations of search algorithms. The state of the object that is returned may or may not be identical to that of the original. Thus, this is a distinct concept from the functionality of the Copyable interface. Classes that implement this interface must ensure that the object returned performs the same functionality, and that it does not share any state data that would be either unsafe or inefficient for concurrent access by multiple threads. The split method is allowed to simply return the this reference, provided that it is both safe and efficient for multiple threads to share a single copy of the Splittable object. The intention is to provide a multithreaded search with the capability to provide spawned threads with their own distinct search operators. Such multithreaded algorithms can call the split method for each thread it spawns to generate a functionally identical copy of the operator, but with independent state.
      Specified by:
      split in interface Splittable<Initializer<SingleReal>>
      Returns:
      A functionally identical copy of the object, or a reference to this if it is both safe and efficient for multiple threads to share a single instance of this Splittable object.