public GraphNode(ISymbolicExpressionTreeNode node, string label)
 {
     SymbolicExpressionTreeNode = node;
     Label  = label;
     Hash   = GetHashCode();
     Depth  = node.GetDepth();
     Length = node.GetLength();
 }
コード例 #2
0
        public static void PTC2(IRandom random, ISymbolicExpressionTreeNode seedNode,
                                int maxLength, int maxDepth)
        {
            // make sure it is possible to create a trees smaller than maxLength and maxDepth
            if (seedNode.Grammar.GetMinimumExpressionLength(seedNode.Symbol) > maxLength)
            {
                throw new ArgumentException("Cannot create trees of length " + maxLength + " or shorter because of grammar constraints.", "maxLength");
            }
            if (seedNode.Grammar.GetMinimumExpressionDepth(seedNode.Symbol) > maxDepth)
            {
                throw new ArgumentException("Cannot create trees of depth " + maxDepth + " or smaller because of grammar constraints.", "maxDepth");
            }

            // tree length is limited by the grammar and by the explicit size constraints
            int allowedMinLength = seedNode.Grammar.GetMinimumExpressionLength(seedNode.Symbol);
            int allowedMaxLength = Math.Min(maxLength, seedNode.Grammar.GetMaximumExpressionLength(seedNode.Symbol, maxDepth));
            int tries            = 0;

            while (tries++ < MAX_TRIES)
            {
                // select a target tree length uniformly in the possible range (as determined by explicit limits and limits of the grammar)
                int targetTreeLength;
                targetTreeLength = random.Next(allowedMinLength, allowedMaxLength + 1);
                if (targetTreeLength <= 1 || maxDepth <= 1)
                {
                    return;
                }

                bool success = TryCreateFullTreeFromSeed(random, seedNode, targetTreeLength - 1, maxDepth - 1);

                // if successful => check constraints and return the tree if everything looks ok
                if (success && seedNode.GetLength() <= maxLength && seedNode.GetDepth() <= maxDepth)
                {
                    return;
                }
                else
                {
                    // clean seedNode
                    while (seedNode.Subtrees.Any())
                    {
                        seedNode.RemoveSubtree(0);
                    }
                }
                // try a different length MAX_TRIES times
            }
            throw new ArgumentException("Couldn't create a random valid tree.");
        }
コード例 #3
0
        public static Tuple <string, int, int, int> CalculateGeneticMaterialChange(ISymbolicExpressionTree child, ItemArray <ISymbolicExpressionTree> parents)
        {
            Tuple <ISymbolicExpressionTreeNode, int> crossoverPoint = FindCrossoverPoint(child, parents[0]);

            if (crossoverPoint == null)
            {
                return(new Tuple <string, int, int, int>(NOCHANGE, 0, 0, 0));
            }

            ISymbolicExpressionTreeNode crossoverPointNode = crossoverPoint.Item1;

            //may be needed to check difference to parent subtree, otherwise delete
            //int indexOfCrossoverPoint = child.Root.IterateNodesBreadth().ToList().IndexOf(crossoverPointNode);
            //var parentSubtree = parents[0].Root.IterateNodesBreadth().ToList()[indexOfCrossoverPoint];

            return(new Tuple <string, int, int, int>(crossoverPointNode.Symbol.Name, crossoverPointNode.GetDepth(), crossoverPointNode.GetLength(), crossoverPoint.Item2));
        }
コード例 #4
0
    public static void PTC2(IRandom random, ISymbolicExpressionTreeNode seedNode,
      int maxLength, int maxDepth) {
      // make sure it is possible to create a trees smaller than maxLength and maxDepth
      if (seedNode.Grammar.GetMinimumExpressionLength(seedNode.Symbol) > maxLength)
        throw new ArgumentException("Cannot create trees of length " + maxLength + " or shorter because of grammar constraints.", "maxLength");
      if (seedNode.Grammar.GetMinimumExpressionDepth(seedNode.Symbol) > maxDepth)
        throw new ArgumentException("Cannot create trees of depth " + maxDepth + " or smaller because of grammar constraints.", "maxDepth");

      // tree length is limited by the grammar and by the explicit size constraints
      int allowedMinLength = seedNode.Grammar.GetMinimumExpressionLength(seedNode.Symbol);
      int allowedMaxLength = Math.Min(maxLength, seedNode.Grammar.GetMaximumExpressionLength(seedNode.Symbol, maxDepth));
      int tries = 0;
      while (tries++ < MAX_TRIES) {
        // select a target tree length uniformly in the possible range (as determined by explicit limits and limits of the grammar)
        int targetTreeLength;
        targetTreeLength = random.Next(allowedMinLength, allowedMaxLength + 1);
        if (targetTreeLength <= 1 || maxDepth <= 1) return;

        bool success = TryCreateFullTreeFromSeed(random, seedNode, targetTreeLength - 1, maxDepth - 1);

        // if successful => check constraints and return the tree if everything looks ok        
        if (success && seedNode.GetLength() <= maxLength && seedNode.GetDepth() <= maxDepth) {
          return;
        } else {
          // clean seedNode
          while (seedNode.Subtrees.Any()) seedNode.RemoveSubtree(0);
        }
        // try a different length MAX_TRIES times
      }
      throw new ArgumentException("Couldn't create a random valid tree.");
    }