Question

我已经获得了一个基本的文本文件，我需要在python中使用正则表达式来拉取每一行的所有单词并打印每行的单词数。

文本文件示例：

I have a dog.
She is small and cute,
and likes to play with other dogs.

示例输出：

Line 1: 4
Line 2: 5
Line 3: 7

任何帮助将不胜感激！

Answer 1

您可以尝试拆分行

with open('input_file_name.txt') as input_file:
line_number = 1
for line in input_file.readlines():
    print( 'Line {} : {}'.format(line_number,len(line.split(' '))))
    line_number +=1

Answer 2

f = open(path_to_text_file, "r") 
counter = 1
for line in f.readlines():  # read the file line by line
    print "Line %d: %d" % (counter, len(line.split(" ")))  # counts the spaces, assuming that there is only one space between words.
    counter += 1

Answer 3

默认情况下，您可以尝试使用awk分割白色空间：

cat <<EOT | awk '{print NF}'
> I have a dog.
> She is small and cute,
> and likes to play with other dogs.
> EOT
4
5
7

NF是一个awk变量，始终设置为当前记录中的字段数。

Answer 4

这个非常直观的正则表达式可能有所帮助：

\b\w+\b

它匹配单词边界之间的所有单词字符。你只需要计算有多少匹配。

如果要将带有连字符（或任何其他字符）的单词计为1个单词，请将-添加到字符集中：

\b[\w\-]\b

或

\b[\w\-'.]\b

等

你明白了。

如何使用正则表达式在多行文本文件中打印每行的长度？

4 个答案: