2012-03-09 96 views
1

我很好奇什麼是最好的方法來處理標記化/索引術語(在Lucene中)或任何搜索引擎,以便這些搜索匹配相應的術語。搜索索引 - 12 =十二

「12」= 「十二條」

「MX1」= 「MX一個」

是否有任何內置的功能,我忽略了?

回答

1

Lucene最簡單的方法是創建2個獨立的令牌過濾器,在初始字符串被標記後使用。第一個需要在數字序列和非數字序列之間進行分割。然後第二個將數字(數字字符串)轉換爲它們的數字(拼寫)數字。

下面是與PyLucene(不包括偏移和位置屬性的邏輯)的例子:

class AlphaNumberBoundaryFilter(lucene.PythonTokenFilter): 
    seq = re.compile(r"((?:\d+")|(?:\D+))") 

    def __init__(self, in_stream): 
     lucene.PythonTokenFilter.__init__(self, in_stream) 
     term = self.term = self.addAttribute(lucene.TermAttribute.class_) 
     # Get tokens. 
     tokens = [] 
     while in_stream.incrementToken(): 
      tokens.append(term.term()) 
     # Filter tokens. 
     self.tokens = self.filter(tokens) 
     # Setup iterator. 
     self.iter = iter(self.tokens) 

    def filter(self, tokens): 
     seq = self.seq 
     return [split for token in tokens for split in seq.findall(token)] 

    def incrementToken(self): 
     try: 
      self.term.setTermBuffer(next(self.iter)) 
     except StopIteration: 
      return False 
     return True 


class NumberToWordFilter(lucene.PythonTokenFilter): 
    num_map = {0: "zero", 1: "one", 2: "two", 3: "three", 4: "four", 5: "five", 6: "six", 7: "seven", 8: "eight", 9: "nine", 10: "ten", 11: "eleven", 12: "twelve", 13: "thirteen", 14: "fourteen", 15: "fifteen", 16: "sixteen", 17: "seventeen", 18: "eighteen", 19: "nineteen", 20: "twenty", 30: "thirty", 40: "forty", 50: "fifty", 60: "sixty", 70: "seventy", 80: "eighty", 90: "ninety", 100: "hundred", 1000: "thousand", 1000000: "million"} 
    is_num = re.compile(r"^\d+$") 

    def __init__(self, in_stream): 
     lucene.PythonTokenFilter.__init__(self, in_stream) 
     term = self.term = self.addAttribute(lucene.TermAttribute.class_) 
     # Get tokens. 
     tokens = [] 
     while in_stream.incrementToken(): 
      tokens.append(term.term()) 
     # Filter tokens. 
     self.tokens = self.filter(tokens) 
     # Setup iterator. 
     self.iter = iter(self.tokens) 

    def filter(self, tokens): 
     num_map = self.num_map 
     is_num = self.is_num 
     final = [] 
     for token in tokens: 
      if not is_num.match(token): 
       final.append(token) 
       continue 
      # Reverse digits from token. 
      digits = token.lstrip('0')[::-1] 
      if not digits: 
       # We have a zero. 
       final.append(num_map[0]) 
       continue 
      # Group every 3 digits and iterate over digit groups in reverse 
      # so that groups are yielded in the original order and in each 
      # group: 0 -> ones, 1 -> tens, 2 -> hundreds 
      groups = [digits[i:i+3] for i in xrange(0, len(digits), 3)][::-1] 
      scale = len(groups) - 1 
      result = [] 
      for oth in groups: 
       l = len(oth) 
       if l == 3 and oth[2] != '0': 
        # 2 -> x 
        # 1 -> . 
        # 0 -> . 
        result.append(num_map[int(oth[2])]) 
        result.append(num_map[100]) 
       if l >= 2: 
        if oth[1] == '1': 
         # 1 -> 1 
         # 0 -> x 
         result.append(num_map[int(oth[1::-1])]) 
        else: 
         if oth[1] != '0': 
          # 1 -> x (x >= 2) 
          # 0 -> x 
          result.append(num_map[int(oth[1]) * 10]) 
         if oth[0] != '0': 
          result.append(num_map[int(oth[0])]) 
       elif oth[0] != '0': 
        # 0 -> x 
        result.append(num_map[int(oth[0])]) 
       # Add scale modifier. 
       s = scale 
       if s % 2: 
        result.append(num_map[1000]) 
       while s >= 2: 
        result.append(num_map[1000000]) 
        s -= 2 
       scale -= 1 
      final.extend(result) 
     return final 


    def incrementToken(self): 
     try: 
      self.term.setTermBuffer(next(self.iter)) 
     except StopIteration: 
      return False 
     return True 
1

你看過Lucene SynonymFilter

+0

會不會使用SynonymFilter與SynonymMap需要你提前適應每一種可能的映射? – 2012-03-10 18:12:27

+0

是的。但是,在使用同義詞時,由於IDF的原因,您最好提前做些事情。見http://stackoverflow.com/questions/7272368/change-dynamically-elasticsearch-synonyms/7273651#7273651 – jpountz 2012-03-19 15:12:31