在CSV的Column中搜索模式，并使用sed命令替换同一行中的另一个模式

问题描述

我想在CSV文件的第二列中检查一个模式(仅当模式开头时)，如果该模式存在，则替换同一行中的其他内容.

I want to check for a pattern (only if the pattern starts with) in second column in a CSV file and if that pattern exists then replace something else in same line.

我写了下面的sed命令，用于在csv之后将I更改为N(如果第二列中存在模式676).但是，由于存在676，因此也会在第7列和第9列中检查676.理想情况下，如果前缀676存在，我只希望检查第二行.我要检查的是第二列中的676前缀(模式不在第二个值Ex-46769777的中间或结尾)，然后对I进行更改.

I wrote the following sed command for following csv to change the I to N if the pattern 676 exists in second column. But it checks 676 in the 7th and 9th column also since the ,676 exists. Ideally, I want only the second line to be checked for if the prefix 676 exists. All I want is to check 676 prefixed in second column (pattern not in the middle or end of the second value Ex- 46769777) and then do the change on ,I, to ,N,.

sed -i  '/,676/ {; s/,I,/,N,/;}' temp.csc

6768880,55999777,S,I,TTTT,I,67677,yy
6768880,676999777,S,I,TTTT,I,67677,yy 
6768880,46769777,S,I,TTTT,I,67677,yy  

需要预期的结果

6768880,55999777,S,I,TTTT,I,67677,yy
6768880,676999777,S,N,TTTT,N,67677,yy
6768880,40999777,S,I,TTTT,I,67677,yy  

推荐答案

这要求在进行任何更改之前， 676 出现在第二列的开头:

This requires that 676 appear at the beginning of the second column before any changes are made:

$ sed   '/^[^,]*,676/ s/,I,/,N,/g' file
6768880,55999777,S,I,TTTT,I,67677,yy
6768880,676999777,S,N,TTTT,N,67677,yy 
6768880,46769777,S,I,TTTT,I,67677,yy  

注意:

• 正则表达式/^ [^，] *，676/要求 676 在该行上首次出现逗号后出现.更详细地:

• The regex /^[^,]*,676/ requires that 676 appear after the first appearance of a comma on the line. In more detail:

• ^ 匹配行的开头

[^，] * 匹配第一列

，676 与第一个逗号匹配，后跟 676

,676 matches the first comma followed by 676

在所需的输出中，每次出现在行中时，，I，都会被替换为，N，.为此，将 g (表示全局)添加到了替代命令中.

In your desired output, ,I, was replaced with ,N, every time it appeared on the line. To accomplish this, g (meaning global) was added to the substitute command.

这篇关于在CSV的Column中搜索模式，并使用sed命令替换同一行中的另一个模式的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！