Class SimpleTable

All Implemented Interfaces:
SatisfiedPresent, Stateful, UsesQueueVariable

public class SimpleTable extends Constraint implements UsesQueueVariable, Stateful, SatisfiedPresent
SimpleTable implements the table constraint using a method presented in

"Compact-Table: Efficient Filtering Table Constraints with Reversible Sparse Bit-Sets" Jordan Demeulenaere, Renaud Hartert, Christophe Lecoutre, Guillaume Perez, Laurent Perron, Jean-Charles Régin, Pierre Schaus. Proc. International Conference on Principles and Practice of Constraint Programming, CP 2016. pp 207-223

Version:
4.10
  • Field Details

    • store

      Store store
    • x

      public IntVar[] x
      Variables within the scope of table constraint
    • tuple

      public int[][] tuple
      Tuples specifying the allowed values
    • words

      TimeStamp<Long> words
      Main data structure for the constraint
    • mask

      long mask
    • varMap

      Map<IntVar,Integer> varMap
    • supports

      Map<Integer,Long>[] supports
      Data specifying support tuples for each variable; static structure created once when constraint is posed.
    • variableQueue

      Set<IntVar> variableQueue
    • noNoGround

      int noNoGround
    • idNumber

      static AtomicInteger idNumber
    • debug

      static final boolean debug
      See Also:
  • Constructor Details

    • SimpleTable

      public SimpleTable(IntVar[] list, int[][] tuples)
      It constructs a table constraint.
      Parameters:
      list - the variables in the scope of the constraint.
      tuples - the tuples which define alloed values.
    • SimpleTable

      public SimpleTable(IntVar[] list, int[][] tuples, boolean reuseTupleArguments)
      It constructs a table constraint.
      Parameters:
      list - the variables in the scope of the constraint.
      tuples - the tuples which define allowed values.
      reuseTupleArguments - specifies if the tuples argument should be used directly without copying.
  • Method Details

    • validTuple

      boolean validTuple(int index)
    • 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 Constraint
      Parameters:
      store - the constraint store to which the constraint is imposed to.
    • 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.
    • updateTable

      void updateTable(Set<IntVar> fdvs)
    • intersectWithMask

      boolean intersectWithMask()
    • filterDomains

      void filterDomains()
    • queueVariable

      public void queueVariable(int level, Var v)
      Description copied from class: Constraint
      This is a function called to indicate which variable in a scope of constraint has changed. It also indicates a store level at which the change has occurred.
      Overrides:
      queueVariable in class Constraint
      Parameters:
      level - the level of the store at which the change has occurred.
      v - variable which has changed.
    • 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.

      Specified by:
      satisfied in interface SatisfiedPresent
      Returns:
      true if constraint is possible to verify that it is satisfied.
    • removeLevel

      public void removeLevel(int level)
      Description copied from interface: Stateful
      This function is called in case of the backtrack, so a constraint can clear the queue of changed variables which is no longer valid. This function is called *before* all timestamps, variables, mutablevariables have reverted to their previous value.
      Specified by:
      removeLevel in interface Stateful
      Parameters:
      level - the level which is being removed.
    • toString

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