python - Python-从字符串中删除停用词

创建从字符串输入中删除停止字的代码时遇到问题目前，我的代码是：

stopWords = [ "a", "i", "it", "am", "at", "on", "in", "to", "too", "very", \
                 "of", "from", "here", "even", "the", "but", "and", "is", "my", \
                 "them", "then", "this", "that", "than", "though", "so", "are" ]
stemEndings = [ "-s", "-es", "-ed", "-er", "-ly" "-ing", "-'s", "-s'" ]
punctuation = [ ".", ",", ":", ";", "!", "?" ]
line = raw_input ("Type in lines, finish with a . at start of line only:")
while line != ".":
    def remove_punctuation(input): #removes punctuation from input
        output = ""
        text= 0
        while text<=(len(input)-1) :
            if input[text] not in punctuation:
               output=output + input[text]
            text+=1
        return output
    newline= remove_punctuation(line)
    newline= newline.lower()

可以添加哪些代码来根据上面的停止字列表从字符串中删除停止字？提前谢谢你。

最佳答案

正如greg建议的那样，应该使用for循环而不是while循环，因为它更像是python，而且更易于理解代码另外，您应该在输入的while循环之前声明函数，这样python解释器就不会每次都重新定义函数了！
此外，如果需要，可以将标点设置为astring，而不是alist（以便于阅读和使用）

stopWords = [ "a", "i", "it", "am", "at", "on", "in", "to", "too", "very", \
              "of", "from", "here", "even", "the", "but", "and", "is", "my", \
              "them", "then", "this", "that", "than", "though", "so", "are" ]
stemEndings = [ "-s", "-es", "-ed", "-er", "-ly" "-ing", "-'s", "-s'" ]
punctuation = ".,:;!?"

def remove_punctuation(input_string):
    for item in punctuation:
        input_string = input_string.replace(item, '')
    return input_string

line = raw_input ("Type in lines, finish with a . at start of line only:")

while not line == ".":
    newline = remove_punctuation(line)
    newline = newline.lower()