protected double[] GoalValueDistribution(Item item, Node node)
{
if (node.IsLeaf())
{
return(((LeafNode)node).GoalValueDistribution);
}
else
{
if (node is TestNode)
{
TestNode tNode = (TestNode)node;
int testAttrIndex = _attributeSet.IndexOf(tNode.Test.Attribute);
if (item.ValueOf(testAttrIndex).IsUnknown())
{
int nbValues = item.NumberOfAttributes();
double[] distr = new double[nbValues];
for (int i = 0; i < nbValues; i++)
{
distr[i] = 0.0d;
}
for (int i = 0; i < tNode.NumOfSons(); i++)
{
Add(distr, Times(
GoalValueDistribution(item, tNode.Son(i)),
tNode.Son(i).Weight));
Times(distr, 1.0 / tNode.Weight);
}
return(distr);
}
else
{
Node nextNode = tNode.MatchingSon(item.ValueOf(testAttrIndex));
return(GoalValueDistribution(item, nextNode));
}
}
}
throw new InvalidOperationException("Open node found while exploring tree.");
}
/// <summary>
/// Find the leaf/Open node matching an item. All the (tested)attributes of the item
/// must be known.
/// </summary>
/// <param name="item">An item compatible with the tree attribute set.</param>
/// <returns>The leaf node matching item</returns>
public Node LeafNode(Item item)
{
if (_attributeSet == null || _goalAttribute == null)
{
throw new InvalidOperationException("No attribute set or goal attribute defined.");
}
AttributeSet attrSet = _attributeSet;
Node node = Root();
while (!(node.IsLeaf()))
{
TestNode testNode = (TestNode)node;
int testAttrIndex = attrSet.IndexOf(testNode.Test.Attribute);
node = testNode.MatchingSon(item.ValueOf(testAttrIndex));
}
return(node);
}
/// <summary>
/// Return the value of an attribute
/// </summary>
/// <param name="attrs"></param>
/// <param name="attribute"></param>
/// <returns></returns>
public AttributeValue ValueOf(AttributeSet attrs, Attribute attribute)
{
return(this.ValueOf(attrs.IndexOf(attribute)));
}