Example #1
0
def parse_binary_search(sent_len, scorer, m):
    def binary_search(seq, t):
        min = -10
        max = 10
        for i in range(25):
            if max < min:
                return -1
            m = (min + max) / 2.0

            size = seq(m)
            #print t, m, size
            if size < t:
                min = m
            elif size > t:
                max = m
            else:
                return m
        return m
    c = Chart(sent_len+1)
    interface.Parser().parse_bigram(sent_len, scorer, None, c)
    counts = c.counts()

    # hypergraph = c.hypergraph
    # pot = c.pot


    # def score(label, tail_size):
    #     typ, d, s, t, _ = label
    #     if typ == interface.Trap:
    #         if d == interface.Left: s, t = t, s
    #         return scorer.arc_score(s, t)
    #     if typ == interface.Tri and d == interface.Right and tail_size == 1:
    #         return scorer.bigram_score(s, t+1) - \
    #             ((t+1 - s - 1) * scorer.skip_penalty) if s != t+1 else 0.0
    #     return 0.0

    def f(pen):
        scorer.skip_penalty = pen
        # c.score = score
        parse = interface.make_parse(sent_len+1, c.regen(pen, counts))
        return sent_len - parse.skipped_words()

    pen = binary_search(f, m)
    scorer.skip_penalty = pen
    return interface.make_parse(sent_len+1, c.regen(pen, counts))
Example #2
0
 def f(pen):
     scorer.skip_penalty = pen
     # c.score = score
     parse = interface.make_parse(sent_len+1, c.regen(pen, counts))
     return sent_len - parse.skipped_words()