/**
* Add a node to the tree.
*
* @param DecisionTree_Node $node
*/
function addNode(DecisionTree_Node $node)
{
$id = $node->getId();
if (isset($this->nodes[$id])) {
throw new Exception("Node with id " . $node->id() . " is already part of the tree.");
}
$node->_bind($this);
$this->nodes[$id] = $node;
}
