internal string Evaluate(RandomTreeNode node, RandomForestInstance instance)
{
var stack = new Stack <RandomTreeNode>();
stack.Push(node);
while (stack.Any())
{
var next = stack.Pop();
if (next.Evaluate(instance))
{
// its not a leaf
if (next.OutputClass == null)
{
foreach (var child in next.Children)
{
stack.Push(child);
}
}
// its a leaf
else
{
return(next.OutputClass);
}
}
}
// tree could not classify instance...
return(RandomTreeNode.NoClass);
}
private void LogTree(RandomTreeNode root)
{
var stack = new Stack <RandomTreeNode>();
stack.Push(root);
while (stack.Any())
{
var next = stack.Pop();
next.LogNode();
foreach (var child in next.Children)
{
stack.Push(child);
}
}
}
internal static RandomTreeNode BuildFromString(string predicateLine, int id, int precision)
{
var node = new RandomTreeNode
{
// get the level, i.e., the number of '|' in the string
Level = DetermineLevel(predicateLine),
Id = id
};
// parse predicate. They look like: | AvgDepsForOutputPips < 3446.5
// or: AvgTagCountForOutputPips < 10.13 : Shared (4/1)
var predicateText = predicateLine.Substring(predicateLine.Contains("|") ? predicateLine.LastIndexOf("|") + 1 : 0).Trim();
// now, split by spaces
var pieces = predicateText.Split(' ');
// here, 0 is the name, 1 is the op and 2 is the value
node.EvaluationPredicate = PredicateBuilder.BuildPredicate(pieces[0], pieces[1], pieces[2], precision);
// now, check if this outputs something
if (predicateLine.Contains(":"))
{
node.OutputClass = pieces[4];
}
return(node);
}
internal static RandomTree FromStream(StreamReader reader, string firstLine, int nodePrecision, int id)
{
var output = new RandomTree()
{
Id = id
};
var keepReading = true;
RandomTreeNode previous = null;
int initialId = 0;
bool first = true;
while (keepReading)
{
++initialId;
try
{
var line = first ? firstLine : reader.ReadLine();
var node = RandomTreeNode.BuildFromString(line, initialId, nodePrecision);
output.NumNodes = +1;
if (node.Level == 0)
{
// for roots
output.Roots.Add(node);
previous = node;
first = false;
}
else
{
// count the levels
if (node.Level > previous.Level)
{
// child
previous.Children.Add(node);
node.Parent = previous;
}
else if (node.Level < previous.Level)
{
// predecessor: travel backwards and look for the first parent with level = level
while (previous != null)
{
if (previous.Level == node.Level - 1)
{
// we found its parent
previous.Children.Add(node);
node.Parent = previous;
break;
}
previous = previous.Parent;
}
}
else
{
// same level, they are siblings
previous.Parent.Children.Add(node);
node.Parent = previous.Parent;
}
previous = node;
}
}
#pragma warning disable ERP022
catch (Exception)
{
// we could not read, so we are in the line after we finished.. how do we know? cause we could not build a predicate
break;
}
#pragma warning disable ERP022
}
// done...
return(output);
}