/// <summary>
/// Loads the forest from the forest file, for example, .INF file.
/// </summary>
/// <param name="forestFileName">The location of the input file.</param>
/// <returns>DecisionForest.</returns>
public DecisionForest Load(string forestFileName)
{
Helper.ThrowIfNull(forestFileName);
bool quesSection = true;
bool treeSection = false;
Collection<string> treeLines = new Collection<string>();
foreach (string line in Helper.FileLines(forestFileName, Encoding.ASCII, false))
{
// Load question sets and count decision tree
if (quesSection)
{
if (line.IndexOf(Question.QuestionKeyword, StringComparison.Ordinal) < 0)
{
quesSection = false;
}
else
{
Question question = new Question(line);
_nameIndexedQuestions.Add(question.Name, question);
}
}
if (!quesSection)
{
string trimLine = line.Trim();
if (!string.IsNullOrEmpty(trimLine))
{
// tree start
if (!treeSection)
{
treeSection = true;
treeLines.Clear();
}
treeLines.Add(trimLine);
}
else
{
// tree end
if (treeSection)
{
DecisionTree tree = new DecisionTree();
tree.Load(treeLines);
_treeList.Add(tree);
treeSection = false;
}
}
}
}
if (treeSection)
{
throw new InvalidDataException(
Helper.NeutralFormat("Invalidate last line for Decision Tree {0}", forestFileName));
}
return this;
}
/// <summary>
/// Gets the selective tri-phone for each leaf nodes in the tree.
/// </summary>
/// <param name="tree">The given tree.</param>
/// <param name="questions">The related questions.</param>
/// <param name="phonemes">The whole set of phoneme, which is used to initialize the tri-phone pairs.</param>
/// <returns>The selective tri-phone for each leaf node in decision tree.
/// The key is the leaf node, and the tri-phone pair set is the value.</returns>
private static Dictionary<DecisionTreeNode, TriphoneSet> GetSelectiveTriphone(DecisionTree tree, IDictionary<string, Question> questions, HashSet<string> phonemes)
{
Dictionary<DecisionTreeNode, TriphoneSet> nodeToTriphone = new Dictionary<DecisionTreeNode, TriphoneSet>();
// Firstly, generate a whole tri-phone set.
TriphoneSet set = new TriphoneSet(phonemes);
// Phone-dependent tree should resize the central phone set.
string phone = tree.Phone;
if (!Phoneme.IsAnyPhone(phone))
{
set.CentralPhones.Clear();
set.CentralPhones.Add(phone);
}
// Assign the tri-phone set to the root of the tree.
nodeToTriphone.Add(tree.NodeList[0], set);
GetSelectiveTriphone(nodeToTriphone, questions);
return nodeToTriphone;
}