/// <summary>
/// Make transition to the next state for the given characteristic vector
/// </summary>
/// <param name="vector">Vector.</param>
public void NextState(int vector)
{
AutomatonState s = GetNextState(vector);
if (s != null)
{
CurrentOffset = s.Offset;
CurrentState = s.State;
UpdateMatricies();
}
else
{
CurrentState = -1;
CurrentOffset = -1;
}
}
/// <summary>
/// Basic Schulz and Mihov algoritm
/// </summary>
/// <returns>The correction nodes.</returns>
/// <param name="typo">Typo.</param>
/// <param name="start">Start.</param>
/// <param name="editDistance">Edit distance.</param>
/// <param name="includeOnlyWords">If set to <c>true</c> include only words.</param>
IList <TrieNode> GetCorrectionNodes(string typo, TrieNode start, int editDistance, bool includeOnlyWords = true)
{
var corrections = new List <TrieNode> ();
if (string.IsNullOrEmpty(typo))
{
return(corrections);
}
LevTAutomataImitation automata = new LevTAutomataImitation(typo, editDistance);
Stack <SpellCheckerState> stack = new Stack <SpellCheckerState> ();
stack.Push(new SpellCheckerState()
{
Node = start,
AutomataState = 0,
AutomataOffset = 0,
});
while (stack.Count > 0)
{
SpellCheckerState state = stack.Pop();
automata.LoadState(state.AutomataState, state.AutomataOffset);
AutomatonState nextZeroState = automata.GetNextState(0);
foreach (char c in state.Node.Children.Keys)
{
AutomatonState nextState = null;
if ((state.AutomataOffset < typo.Length && typo[state.AutomataOffset] == c) ||
(state.AutomataOffset < typo.Length - 1 && typo[state.AutomataOffset + 1] == c) ||
(state.AutomataOffset < typo.Length - 2 && typo[state.AutomataOffset + 2] == c))
{
nextState = automata.GetNextState(automata.GetCharacteristicVector(c, state.AutomataOffset));
}
else
{
nextState = nextZeroState;
}
if (nextState != null)
{
TrieNode nextNode = state.Node.Children [c];
if (nextNode.Children.Count > 0)
{
stack.Push(new SpellCheckerState()
{
Node = nextNode,
AutomataState = nextState.State,
AutomataOffset = nextState.Offset
});
}
if ((nextNode.IsWord || !includeOnlyWords) && automata.IsAcceptState(nextState.State, nextState.Offset))
{
corrections.Add(nextNode);
}
}
}
}
return(corrections);
}
