Linux 简单的 awk 命令问题（FS、OFS 相关）
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Simple awk command issue (FS, OFS related)
提问by olala
I tried to reorganize the format of a file containing:
我试图重新组织包含以下文件的格式：
>Humanl|chr16:86430087-86430726 | element 1 | positive
>Humanl|chr16:85620095-85621736 | element 2 | negative
>Humanl|chr16:80423343-80424652 | element 3 | negative
>Humanl|chr16:80372593-80373755 | element 4 | positive
>Humanl|chr16:79969907-79971297 | element 5 | negative
>Humanl|chr16:79949950-79951518 | element 6 | negative
>Humanl|chr16:79026563-79028162 | element 7 | negative
>Humanl|chr16:78933253-78934686 | element 9 | negative
>Humanl|chr16:78832182-78833595 | element 10 | negative
My command is:
我的命令是：
awk '{FS="|";OFS="\t"} {print ,,,,}'
Here is the output:
这是输出：
>Human|chr16:86430087-86430726 | element 1 |
>Human chr16:85620095-85621736 element 2 negative
>Human chr16:80423343-80424652 element 3 negative
>Human chr16:80372593-80373755 element 4 positive
>Human chr16:79969907-79971297 element 5 negative
>Human chr16:79949950-79951518 element 6 negative
>Human chr16:79026563-79028162 element 7 negative
>Human chr16:78933253-78934686 element 9 negative
>Human chr16:78832182-78833595 element 10 negative
Every line works fine except for the first line. I don't understand why this happened.
除了第一行之外，每一行都可以正常工作。我不明白为什么会这样。
Can someone help me with it? Thanks!
有人可以帮我吗？谢谢！
采纳答案by Thor
Short answer
简答
FSand OFSare set too late to affect the first line, use something like this instead:
FS并且OFS设置得太晚而无法影响第一行，请改用以下内容：
awk '{print ,,,,}' FS='|' OFS='\t'
You can also use this shorter version:
您还可以使用这个较短的版本：
awk -v FS='|' -v OFS='\t' '='
A bit longer answer
有点长的答案
It doesn't work because awk has already performed record/field splitting at the time when FSand OFSare set. You can force a re-splitting by setting $0to $0, e.g.:
它不起作用，因为 awk 在设置FS和时已经执行了记录/字段拆分OFS。您可以通过设置$0为强制重新拆分$0，例如：
awk '{FS="|";OFS="\t";awk '{print ,,,,}' FS='|' OFS='\t'
=awk 'BEGIN{FS="|";OFS="\t"} {print ,,,,}'
} {print ,,,,}'
The conventional ways to do this are 1. set FSand others in the BEGINclause, 2. set them through the -v VAR=VALUEnotation, or 3. append them after the script as VAR=VALUE. My preferred style is the last alternative:
执行此操作的常规方法是 1.FS在BEGIN子句中设置和其他，2. 通过-v VAR=VALUE符号设置它们，或 3. 将它们附加在脚本之后作为VAR=VALUE。我喜欢的风格是最后一种选择：
Note that there is a significant difference between when -vand post-script variables are set. -vwill set variables before the BEGINclause whilst post-script setting of variables are set just after the BEGINclause.
请注意，-v设置when和 post-script 变量之间存在显着差异。-v将在BEGIN子句之前设置变量，而在子句之后设置变量的脚本后设置BEGIN。
回答by Kent
try:
尝试：
##代码##