Class RandomSelect<T extends Var>

java.lang.Object
org.jacop.search.RandomSelect<T>
All Implemented Interfaces:
SelectChoicePoint<T>

public class RandomSelect<T extends Var> extends Object implements SelectChoicePoint<T>
It is simple and customizable selector of decisions (constraints) which will be enforced by search.
Version:
4.9
  • Field Details

    • debugAll

      static final boolean debugAll
      See Also:
    • searchVariables

      public T extends Var[] searchVariables
    • valueOrdering

      Indomain<T extends Var> valueOrdering
    • position

      public Map<T extends Var,Integer> position
      It stores the original positions of variables to be used for input order tie-breaking.
    • currentIndex

      int currentIndex
    • random

      Random random
  • Constructor Details

    • RandomSelect

      public RandomSelect(T[] variables, Indomain<T> indomain)
      The constructor to create a simple choice select mechanism.
      Parameters:
      variables - variables upon which the choice points are created.
      indomain - the value heuristic to choose a value for a given variable.
  • Method Details

    • getChoiceVariable

      public T getChoiceVariable(int index)
      It returns the variable which is the base on the next choice point. Only if choice is of an X = C type. This function returns null if all variables have a value assigned or a choice point based on other type of constraint is being selected. The parameter index is the last value which have been return by this SelectChoicePoint object which has not been backtracked upon yet.
      Specified by:
      getChoiceVariable in interface SelectChoicePoint<T extends Var>
      Parameters:
      index - the position of the last variable in selection choice point heuristic.
      Returns:
      variable based on which the choice needs to be created.
    • getChoiceValue

      public int getChoiceValue()
      It returns a value which is the base of the next choice point. Only if choice is of an X = C type.
      Specified by:
      getChoiceValue in interface SelectChoicePoint<T extends Var>
      Returns:
      value used in the choice point (value).
    • getChoiceConstraint

      public PrimitiveConstraint getChoiceConstraint(int index)
      It always returns null as choice point is obtained by getChoiceVariable and getChoiceValue.
      Specified by:
      getChoiceConstraint in interface SelectChoicePoint<T extends Var>
      Parameters:
      index - the position of the last variable returned by selection choice point heuristic.
      Returns:
      primitive constraint which is a base of a choice point.
    • getVariablesMapping

      public Map<T,Integer> getVariablesMapping()
      It returns the variables for which assignment in the solution is given.
      Specified by:
      getVariablesMapping in interface SelectChoicePoint<T extends Var>
      Returns:
      mapping of variables to the positions in the variables array.
    • getIndex

      public int getIndex()
      It returns the current index. Supplying this value in the next invocation of select will make search for next variable faster without comprimising efficiency.
      Specified by:
      getIndex in interface SelectChoicePoint<T extends Var>
      Returns:
      internal position of the last variable chosen to be the base of the choice point.
    • placeSearchVariable

      public T placeSearchVariable(int searchPosition, int variablePosition)
      It gets as input the index of the variable which is chosen by search to be instantiated at this stage. The variable is positioned at search position.
      Parameters:
      searchPosition - position at which search store currently choosen variable.
      variablePosition - current position of the variable choosen by search.
      Returns:
      variable choosen to be a base of the choice point.
    • toString

      public String toString()
      Overrides:
      toString in class Object