Python sed 删除“.”之后的所有内容。在文件中使用 * 命令？

Sed to remove everything after "." in file using * command?

提问by Novice

I have the following data.txt:

我有以下 data.txt：

 95 flour.
 47 water.s
 etc..

I need to remove everything after the period . in the file to yield something like this:

我需要在期间后删除所有内容。在文件中产生这样的东西：

 95 flour
 47 water
 etc..

I have tried the using these sed command without success, which yield a blank document:

我已经尝试使用这些 sed 命令但没有成功，这会产生一个空白文档：

sed "s/'.*//" data.txt > cleaned.txt 
sed 's/\.*//' data.txt > cleaned.txt 

采纳答案by Adam Rosenfield

Either escape the .with a backslash to get a literal ., or use brackets to define a character class:

要么.使用反斜杠转义 以获得文字.，要么使用方括号定义字符类：

sed 's/\..*$//' data.txt > cleaned.txt
sed 's/[.].*$//' data.txt > cleaned.txt

You tried 's/\.*//', which is "zero or more literal dots", which is different from "literal dot followed by zero or more of anything", i.e. 's/\..*//'. I also added a $for good measure.

您尝试过's/\.*//'，这是“零个或多个文字点”，这与“文字点后跟零个或多个任何内容”不同，即's/\..*//'. 我还添加了一个$很好的衡量标准。

回答by Novice

This seemed to work:

这似乎有效：

sed "s/[.].*//" data.txt > cleaned.txt

I would be interested to know how this can be done alternatively in bash and python, if anyone wouldn't mind sharing?

我很想知道如何在 bash 和 python 中交替完成，如果有人不介意分享的话？

Thanks!

谢谢！

回答by MK.

This is the simplest:

这是最简单的：

sed "s/\..*//"

And this is, I think, one of the best ways of doing it (better than pure bash or Python).

我认为这是最好的方法之一（比纯 bash 或 Python 更好）。