Exemplo n.º 1
0
 public static List<String> toTagList(List<State> states) {
   List<String> tags = new ArrayList<String>();
   if (states.size() > 0) {
     tags.add(states.get(0).getPreviousPreviousTag());
     for (State state : states) {
       tags.add(state.getPreviousTag());
     }
   }
   return tags;
 }
Exemplo n.º 2
0
 /**
  * Builds a Trellis over a sentence, by starting at the state State, and advancing through all
  * legal extensions of each state already in the trellis. You should not have to modify this
  * code (or even read it, really).
  */
 private Trellis<State> buildTrellis(List<String> sentence) {
   Trellis<State> trellis = new Trellis<State>();
   trellis.setStartState(State.getStartState());
   State stopState = State.getStopState(sentence.size() + 2);
   trellis.setStopState(stopState);
   Set<State> states = Collections.singleton(State.getStartState());
   for (int position = 0; position <= sentence.size() + 1; position++) {
     Set<State> nextStates = new HashSet<State>();
     for (State state : states) {
       if (state.equals(stopState)) continue;
       LocalTrigramContext localTrigramContext =
           new LocalTrigramContext(
               sentence, position, state.getPreviousPreviousTag(), state.getPreviousTag());
       Counter<String> tagScores = localTrigramScorer.getLogScoreCounter(localTrigramContext);
       for (String tag : tagScores.keySet()) {
         double score = tagScores.getCount(tag);
         State nextState = state.getNextState(tag);
         trellis.setTransitionCount(state, nextState, score);
         nextStates.add(nextState);
       }
     }
     //        System.out.println("States: "+nextStates);
     states = nextStates;
   }
   return trellis;
 }
Exemplo n.º 3
0
 // to tag a sentence: build its trellis and find a path through that trellis
 public List<String> tag(List<String> sentence) {
   Trellis<State> trellis = buildTrellis(sentence);
   List<State> states = trellisDecoder.getBestPath(trellis);
   List<String> tags = State.toTagList(states);
   tags = stripBoundaryTags(tags);
   return tags;
 }
Exemplo n.º 4
0
 private State(State state) {
   setState(state.getPreviousPreviousTag(), state.getPreviousTag(), state.getPosition());
 }
Exemplo n.º 5
0
 public State getPreviousState(String tag) {
   return State.buildState(tag, getPreviousPreviousTag(), getPosition() - 1);
 }
Exemplo n.º 6
0
 public State getNextState(String tag) {
   return State.buildState(getPreviousTag(), tag, getPosition() + 1);
 }
Exemplo n.º 7
0
 public static State buildState(String previousPreviousTag, String previousTag, int position) {
   tempState.setState(previousPreviousTag, previousTag, position);
   return stateInterner.intern(tempState);
 }