Package org.jreliability.bdd

Class BDDs

java.lang.Object
org.jreliability.bdd.BDDs
public abstract class BDDs extends Object
The BDDs contains common reliabilityFunctions for/on BDDs.

  • Field Details

    • NEWLINE

      protected static final String NEWLINE
      The platform-independent newline symbol.

  • Constructor Details

    • BDDs

      public BDDs()

  • Method Details

    • getVariables

      public static <T> Set<T> getVariables(BDD<T> bdd)
      Returns all variables (elements) T included in the BDD.
      Type Parameters:
      T - the type of variables
      Parameters:
      bdd - the bdd
      Returns:
      all variables T included in the bdd

    • getNodes

      public static <T> Set<BDD<T>> getNodes(T t, BDD<T> bdd)
      Returns all nodes of the BDD that represent the variable T.
      Type Parameters:
      T - the type of variable
      Parameters:
      t - the variable
      bdd - the bdd
      Returns:
      all nodes in the bdd that represent variable t

    • getBDD

      public static <T> BDD<T> getBDD(List<Integer> coeffs, List<BDD<T>> vars, LinearTerm.Comparator comp, int rhs, BDDProvider<T> provider)
      Converts a linear constraint to a BDD.
      Type Parameters:
      T - the type of variables of the BDD
      Parameters:
      coeffs - the coefficients
      vars - the variables
      comp - the comparator ("<","<=","=",">=",">")
      rhs - the right hand side value
      provider - the bdd provider
      Returns:
      the BDD representing this linear constraint

    • getConstraintBDD

      protected static <T> BDD<T> getConstraintBDD(org.jreliability.bdd.BDDConstraint<T> constraint, BDDProvider<T> provider)
      Returns a greater-equal constraint represented as a BDD.
      Type Parameters:
      T - the type of variables
      Parameters:
      constraint - the greater-equal constraint
      provider - the bdd provider
      Returns:
      the bdd representation of the given constraint

    • toDot

      public static <T> String toDot(BDD<T> bdd)
      Returns a graphical representation of the BDD in the DOT input format.
      Type Parameters:
      T - the type of variable
      Parameters:
      bdd - the bdd
      Returns:
      the bdd as a DOT input string
      See Also:

    • calculateTop

      public static <T> double calculateTop(BDD<T> bdd, org.apache.commons.collections15.Transformer<T,Double> transformer)
      Calculates the top event of the BDD based on a functionTransformer that delivers for each variable T a double value.
      Type Parameters:
      T - the type of variable
      Parameters:
      bdd - the bdd
      transformer - the transformer that returns a double value for each variable
      Returns:
      the top event of the bdd

    • traverseBDD

      protected static <T> void traverseBDD(BDD<T> bdd, Set<BDD<T>> upSort)
      Traverses the BDD to sort the nodes.
      Type Parameters:
      T - the type of variables
      Parameters:
      bdd - the bdd
      upSort - the sorted bdd nodes

    • evaluate

      protected static <T> double evaluate(BDD<T> bdd, org.apache.commons.collections15.Transformer<T,Double> transformer, Set<BDD<T>> upSort)
      Evaluates the BDD to determine the top event.
      Type Parameters:
      T - the type of the variables
      Parameters:
      bdd - the bdd
      transformer - the transformer
      upSort - the sorted bdd nodes
      Returns:
      the top event

    • buildConstraintBDD

      protected static <T> BDD<T> buildConstraintBDD(List<org.jreliability.bdd.BDDConstraint.Literal<T>> literals, int rhs, int index, int sum, int materialLeft, Map<org.jreliability.bdd.BDDConstraint.Pair<Integer,Integer>,BDD<T>> memo, BDDProvider<T> provider)
      Returns a greater-equal constraint represented as a BDD via a recursive procedure proposed by Een & Soerrensson 2006.
      Type Parameters:
      T - the type of variables
      Parameters:
      literals - the literals
      rhs - the right hand side of the constraint
      index - the index
      sum - the current sum
      materialLeft - the material that is potentially left to be added to the sum
      memo - the memo maps each point in the recursion to its bdd
      provider - the used bdd provider
      Returns:
      the bdd representation of the given constraint

    • collectDotNodes

      protected static <T> void collectDotNodes(BDD<T> bdd, StringBuffer dot, Map<BDD<T>,String> variables, Map<T,Integer> counters)
      Traverses the BDD to collects all nodes for the DOT representation.
      Type Parameters:
      T - the type of variables
      Parameters:
      bdd - the bdd
      dot - the dot input
      variables - the used variables
      counters - the used counters for each element

    • collectDotEdges

      protected static <T> void collectDotEdges(BDD<T> bdd, StringBuffer dot, Map<BDD<T>,String> variables, Set<BDD<T>> considered)
      Traverses the BDD to collects all edges for the DOT representation.
      Type Parameters:
      T - the type of variable
      Parameters:
      bdd - the bdd
      dot - the dot input string
      variables - the used variables
      considered - the marker for already considered bdds

    • collectDotMarkers

      protected static <T> void collectDotMarkers(BDD<T> bdd, StringBuffer dot, Map<T,String> markers)
      Traverses the BDD to setup the correct ranks of all nodes belonging to the same variable.
      Type Parameters:
      T - the type of variable
      Parameters:
      bdd - the bdd
      dot - the dot input string
      markers - the marker variables for each variable

    • collectDotRanks

      protected static <T> void collectDotRanks(BDD<T> bdd, StringBuffer dot, Map<BDD<T>,String> variables, Map<T,String> markers)
      Traverses the BDD to setup the correct ranks of all nodes belonging to the same variable.
      Type Parameters:
      T - the type of variable
      Parameters:
      bdd - the bdd
      dot - the dot input
      variables - the used variables
      markers - the marker variables

    • collectVariables

      protected static <T> void collectVariables(BDD<T> bdd, Set<T> variables, Set<BDD<T>> considered)
      Traverses the BDD to collect all variables.
      Type Parameters:
      T - the type of variables
      Parameters:
      bdd - the bdd
      variables - the variables
      considered - the already considered bdds

    • collectVariablesSorted

      protected static <T> void collectVariablesSorted(BDD<T> bdd, List<T> variables)
      Traverses the BDD to collect all variables in the current variable order of the BDD.
      Type Parameters:
      T - the type of variables
      Parameters:
      bdd - the bdd
      variables - the variables

    • collectNodes

      protected static <T> void collectNodes(BDD<T> bdd, T t, Set<BDD<T>> considered, Set<BDD<T>> nodes)
      Traverses the BDD to collect all nodes for a given variable T.
      Type Parameters:
      T - the type of variables
      Parameters:
      bdd - the bdd
      t - the variable
      considered - the already considered bdds
      nodes - the found nodes