python统计单词出现次数

python统计单词出现次数

做单词词频统计，用字典无疑是最合适的数据类型，单词作为字典的key， 单词出现的次数作为字典的 value，很方便地就记录好了每个单词的频率，字典很像我们的电话本，每个名字关联一个电话号码。

下面是具体的实现代码，实现了从importthis.txt文件读取单词，并统计出现次数最多的5个单词。

# -*- coding:utf-8 -*- import io import re  class Counter:     def __init__(self, path):         """         :param path: 文件路径         """         self.mapping = dict()         with io.open(path, encoding="utf-8") as f:             data = f.read()             words = [s.lower() for s in re.findall("w+", data)]             for word in words:                 self.mapping[word] = self.mapping.get(word, 0) + 1      def most_common(self, n):         assert n > 0, "n should be large than 0"         return sorted(self.mapping.items(), key=lambda item: item[1], reverse=True)[:n]  if __name__ == '__main__':     most_common_5 = Counter("importthis.txt").most_common(5)     for item in most_common_5:         print(item)

执行效果：

('is', 10) ('better', 8) ('than', 8) ('the', 6) ('to', 5)