void AssertGBMNode(GBMNode expected, GBMNode actual)
{
Assert.AreEqual(expected.Depth, actual.Depth);
Assert.AreEqual(expected.FeatureIndex, actual.FeatureIndex);
Assert.AreEqual(expected.LeftConstant, actual.LeftConstant, m_delta);
Assert.AreEqual(expected.LeftError, actual.LeftError, m_delta);
Assert.AreEqual(expected.LeftIndex, actual.LeftIndex);
Assert.AreEqual(expected.RightConstant, actual.RightConstant, m_delta);
Assert.AreEqual(expected.RightError, actual.RightError, m_delta);
Assert.AreEqual(expected.RightIndex, actual.RightIndex);
Assert.AreEqual(expected.SampleCount, actual.SampleCount);
Assert.AreEqual(expected.SplitValue, actual.SplitValue, m_delta);
}
private static List <GBMNode> ConvertXGBoostNodesToGBMNodes(string textTree)
{
var newLine = new string[] { "\n" };
var lines = textTree.Split(newLine, StringSplitOptions.RemoveEmptyEntries);
var nodes = new List <GBMNode>
{
// Add special root node for sharplearning
new GBMNode
{
FeatureIndex = -1,
SplitValue = -1,
LeftConstant = 0.5,
RightConstant = 0.5,
},
};
// Order lines by node index and remove booster line.
var ordered = lines.Where(l => !l.Contains("booster")).ToArray();
var orderedLines = ordered
.OrderBy(l => ParseNodeIndex(l))
.ToDictionary(l => ParseNodeIndex(l), l => l);
var nodeIndex = 1;
foreach (var line in orderedLines.Values)
{
if (IsLeaf(line))
{
// Leafs are not added as nodes, leaf values are included in the split nodes.
continue;
}
else
{
var featureIndex = ParseFeatureIndex(line);
var splitValue = ParseSplitValue(line);
var yesIndex = ParseYesIndex(line);
var noIndex = ParseNoIndex(line);
var node = new GBMNode
{
FeatureIndex = featureIndex,
SplitValue = splitValue,
LeftConstant = -1,
LeftIndex = -1,
RightConstant = -1,
RightIndex = -1
};
var left = orderedLines[yesIndex];
if (IsLeaf(left))
{
node.LeftIndex = -1;
node.LeftConstant = ParseLeafValue(left);
}
else
{
nodeIndex++;
node.LeftIndex = nodeIndex;
}
var right = orderedLines[noIndex];
if (IsLeaf(right))
{
node.RightIndex = -1;
node.RightConstant = ParseLeafValue(right);
}
else
{
nodeIndex++;
node.RightIndex = nodeIndex;
}
nodes.Add(node);
}
}
return(nodes);
}
