public static Node generateFullTree(int maxDepth, Board board, Individual individual)
{
/*
* generate a full grown tree
*/
Node root;
//If we are not at the max depth, choose a function
if (maxDepth > 1)
{
// create new function
root = new Function(false, board, individual.getRandomFunction(), individual);
// create the proper amount of children (according to the function that was just created)
root.children = new Node[root.getNumChildren()];
}
//Otherwise, choose a terminal
else
{
// create new terminal
root = new Terminal(board, individual.getRandomTerminal(), individual);
}
root.height = maxDepth;
//Recursively assign child nodes
for (int i = 0; i < root.getNumChildren(); i++)
{
root.children[i] = Node.generateFullTree(maxDepth - 1, board, individual);
}
// return the created root
return(root);
}
public Individual mutate()
{
/*
* randomly choose a node and swap it with randomly generated tree with max depth of 3
* (not a full tree)
*/
int randNum;
Individual mutatedIndividual = new Individual(this);
const int MIN = 2;
Node mutateNode = null;
Node mutateNodeSwap = null;
randNum = rnd.Next(this.getStrategyRoot().countNodes() - MIN + 1) + MIN;
mutateNode = mutatedIndividual.getStrategyRoot().getNode(mutatedIndividual.getStrategyRoot(), randNum - 1);
if (mutateNode.GetType() == typeof(Terminal))
{
// if the selected node is a terminal,
// set it to another random terminal
((Terminal)mutateNode).setRandTerminal();
}
else
{
// if the selected node is a function,
// generate a random tree (not full) of max depth of 3 and swap the nodes
// need to research other sizes of random generated mutation tree
mutateNodeSwap = Node.generateFullTree(3, board, this);
mutatedIndividual.getStrategyRoot().swapNodes(mutateNode, mutateNodeSwap);
}
return(mutatedIndividual);
}
// Generate a random tree
public bool growRandomTree(int maxDepth)
{
if (root != null)
{
return(false);
}
root = Node.generateFullTree(maxDepth, board, individual);
root.setIsRoot(true);
return(true);
}