Package org.jacop.set.constraints

Class AltB

java.lang.Object
org.jacop.constraints.DecomposedConstraint<Constraint>
org.jacop.constraints.Constraint
org.jacop.constraints.PrimitiveConstraint
org.jacop.set.constraints.AltB
All Implemented Interfaces:
SatisfiedPresent, StoreAware
public class AltB extends PrimitiveConstraint
It creates a < b constraint on two set variables. The set variables are constrained to be lexicographically ordered.

For example, {}<lex {1} {1, 2}<lex {1, 2, 3} {1, 3}<lex {2} {1}< {2}

Version:
4.10

  • Field Details

    • idNumber

      static AtomicInteger idNumber

    • a

      public SetVar a
      It specifies the first variable of the constraint

    • b

      public SetVar b
      It specifies the second variable of the constraint

    • aGEb

      AleB aGEb
      Negated constraint

  • Constructor Details

    • AltB

      public AltB(SetVar a, SetVar b)
      It constructs an Lexical ordering constraint to restrict the domain of the variables a and b. It is strict by default.
      Parameters:
      a - variable that is restricted to be less than b with lexical order.
      b - variable that is restricted to be greater than a with lexical order.

    • AltB

      AltB(SetVar a, SetVar b, boolean negated)
      It constructs an Lexical ordering to be used in negated constrained. Not to be used for imposing constraints.
      Parameters:
      a - variable that is restricted to be less than b with lexical order.
      b - variable that is restricted to be greater than a with lexical order.
      negated - used to distinguish constructors only.

  • Method Details

    • consistency

      public void consistency(Store store)
      Description copied from class: Constraint
      It is a (most probably incomplete) consistency function which removes the values from variables domains. Only values which do not have any support in a solution space are removed.
      Specified by:
      consistency in class Constraint
      Parameters:
      store - constraint store within which the constraint consistency is being checked.

    • setLexLT

      boolean setLexLT(IntDomain x, IntDomain y)

    • notConsistency

      public void notConsistency(Store store)
      Description copied from class: PrimitiveConstraint
      It makes pruning in such a way that constraint is notConsistent. It removes values which always belong to a solution.
      Specified by:
      notConsistency in class PrimitiveConstraint
      Parameters:
      store - the constraint store in which context the notConsistency technique is evaluated.

    • satisfied

      public boolean satisfied()
      Description copied from interface: SatisfiedPresent
      It checks if the constraint is satisfied. It can return false even if constraint is satisfied but not all variables in its scope are grounded. It needs to return true if all variables in its scope are grounded and constraint is satisfied.

      Implementations of this interface for constraints that are not PrimitiveConstraint may require constraint imposition and consistency check as a requirement to work correctly.

      Returns:
      true if constraint is possible to verify that it is satisfied.

    • notSatisfied

      public boolean notSatisfied()
      Description copied from class: PrimitiveConstraint
      It checks if constraint would be always not satisfied.
      Specified by:
      notSatisfied in class PrimitiveConstraint
      Returns:
      true if constraint must be notSatisfied, false otherwise.

    • getDefaultNestedConsistencyPruningEvent

      protected int getDefaultNestedConsistencyPruningEvent()
      Overrides:
      getDefaultNestedConsistencyPruningEvent in class PrimitiveConstraint

    • getDefaultNestedNotConsistencyPruningEvent

      protected int getDefaultNestedNotConsistencyPruningEvent()
      Overrides:
      getDefaultNestedNotConsistencyPruningEvent in class PrimitiveConstraint

    • getDefaultNotConsistencyPruningEvent

      protected int getDefaultNotConsistencyPruningEvent()
      Specified by:
      getDefaultNotConsistencyPruningEvent in class PrimitiveConstraint

    • getDefaultConsistencyPruningEvent

      public int getDefaultConsistencyPruningEvent()
      Specified by:
      getDefaultConsistencyPruningEvent in class Constraint

    • impose

      public void impose(Store store)
      Description copied from class: Constraint
      It imposes the constraint in a given store.
      Overrides:
      impose in class PrimitiveConstraint
      Parameters:
      store - the constraint store to which the constraint is imposed to.

    • toString

      public String toString()
      Description copied from class: Constraint
      It produces a string representation of a constraint state.
      Overrides:
      toString in class Constraint