private void AppendLeaves(GPUNode[] gpuNodes, int nodeIndex, List <GPUNode> leaves)
{
GPUNode node = gpuNodes[nodeIndex];
switch (node.SplitType)
{
case GPUConstants.SplitType_Null:
throw new InvalidOperationException("Null node in tree");
case GPUConstants.SplitType_None:
leaves.Add(node);
break;
case GPUConstants.SplitType_Attribute:
case GPUConstants.SplitType_Categorical:
AppendLeaves(gpuNodes, node.LeftChild, leaves);
AppendLeaves(gpuNodes, node.RightChild, leaves);
break;
default:
throw new InvalidOperationException("Unknown split type: " + node.SplitType);
}
}
private IDataNode ReadDecisionTree(GPUNode[] nodes, int nodeIndex)
{
GPUNode node = nodes[nodeIndex];
switch (node.SplitType)
{
case GPUConstants.SplitType_Null:
throw new InvalidOperationException("Null node in tree");
case GPUConstants.SplitType_None:
return(new DataLeaf {
ClassDistribution = ReadClassDistribution(node.ClassDistribution),
});
case GPUConstants.SplitType_Attribute:
return(new AttributeSplit {
Axis = node.SplitAxis,
SplitValue = node.SplitAttribute,
Left = ReadDecisionTree(nodes, node.LeftChild),
Right = ReadDecisionTree(nodes, node.RightChild),
ClassDistribution = ReadClassDistribution(node.ClassDistribution),
});
case GPUConstants.SplitType_Categorical:
return(new CategoricalSplit {
Axis = node.SplitAxis,
Categories = node.SplitCategories,
Left = ReadDecisionTree(nodes, node.LeftChild),
Right = ReadDecisionTree(nodes, node.RightChild),
ClassDistribution = ReadClassDistribution(node.ClassDistribution),
});
default:
throw new InvalidOperationException("Unknown split type: " + node.SplitType);
}
}