UnboundLocalError：分配前已引用局部变量“ Counter”

Question

这是我的代码

    #word count2
from collections import Counter
def main():
    with open("search words.txt","r") as myfile:
         data=myfile.read()
         topTenWords(data)


def topTenWords(wordCountDict):
    split_it=wordCountDict.split()
    Counter = Counter(split_it)
    most_common=Counter.most_common(10)
    print(most_common)

if __name__=='__main__':
  main()

然后在运行上面的代码时我得到了错误

word count2.py 
Traceback (most recent call last):
  File "D:/word count2.py", line 16, in <module>
    main()
  File "D:/word count2.py", line 6, in main
    topTenWords(data)
  File "D:/word count2.py", line 11, in topTenWords
    Counter = Counter(split_it)
UnboundLocalError: local variable 'Counter' referenced before assignment

上面的代码有什么错误？

Answer 1

您正在用变量覆盖导入的Counter类。 只需编写例如counter = Counter(split_it) ，它应该可以工作。

顺便说一句，您可能想阅读《 PEP8 Python样式指南》，通常您不使用以大写字母开头的变量名称。

Answer 2

这应该工作：

# coding:utf-8
from collections import Counter


def main():
    with open("../docs/words.txt", "r") as myfile:
        data = myfile.read()
        topTenWords(data)
def topTenWords(wordCountDict):
    split_it = wordCountDict.split()
    counter = Counter(split_it)
    most_common = counter.most_common(10)
    print(most_common)


if __name__ == '__main__':
    main()