连接 grep 输出字符串（bash 脚本）

Concatenate grep output string (bash script)

提问by jensG

I'm processing some data from a text file using a bash script (Ubuntu 12.10).

我正在使用 bash 脚本（Ubuntu 12.10）处理来自文本文件的一些数据。

The basic idea is that I select a certain line from a file using grep. Next, I process the line to get the number with sed. Both the grep and sed command are working. I can echo the number.

基本思想是我使用 grep 从文件中选择某一行。接下来，我处理该行以使用 sed 获取数字。grep 和 sed 命令都在工作。我可以回应这个数字。

But the concatenation of the result with a string goes wrong.

但是结果与字符串的连接出错了。

I get different results when combining string when I do a grep command from a variable or a file. The concatenation goes wrong when I grep a file. It works as expected when I grep a variable with the same text as in the file.

当我从变量或文件执行 grep 命令时，组合字符串时得到不同的结果。当我 grep 文件时，连接出错。当我使用与文件中相同的文本 grep 变量时，它按预期工作。

What am I doing wrong with the grep from a file?

我对文件中的 grep 做错了什么？

Contents of test.pdb

test.pdb 的内容

REMARK overall = 324.88  
REMARK bon     = 24.1918  
REMARK coup    = 0  

My script

我的剧本

#!/bin/bash

#Correct function
echo "Working code"
TEXT="REMARK overall = 324.88\nREMARK bon     = 24.1918\nREMARK coup    = 0\n"
DATA=$(echo -e $TEXT | grep 'overall' | sed -n -e "s/^.*= //p" )

echo "Data: $DATA"
DATA="$DATA;0"
echo $DATA


#Not working
echo ""
echo "Not working code"
DATA=$(grep 'overall' test.pdb | sed -n -e "s/^.*= //p")

echo "Data: $DATA"
DATA="$DATA;0"
echo $DATA

Output

输出

Working code
Data: 324.88
324.88;0

Not working code
Data: 324.88
;04.88

采纳答案by Salvatore

I went crazy with the same issue.

我对同样的问题发疯了。

The real problem is that your "test.pdb" has probably a wrong EOL (end of line) character.

真正的问题是您的“test.pdb”可能有错误的 EOL（行尾）字符。

Linux EOL: LF (aka \n)

Linux EOL：LF（又名 \n）

Windows EOL: CR LF (aka \r \n)

Windows EOL：CR LF（又名 \r \n）

This mean that echo and grep will have problem with this extra character (\r), luckily tr, sed and awk manage it correctly.

这意味着 echo 和 grep 会遇到这个额外字符 (\r) 的问题，幸运的是 tr、sed 和 awk 正确管理它。

So you can try also with:

所以你也可以尝试：

DATA=$(grep 'overall' test.pdb | sed -n -e "s/^.*= //p" | sed -e 2s/\r$//")

DATA=$(grep '整体' test.pdb | sed -n -e "s/^.*= //p" | sed -e 2s/\r$//")

or

或者

DATA=$(grep 'overall' test.pdb | sed -n -e "s/^.*= //p" | tr -d '\r')

DATA=$(grep '整体' test.pdb | sed -n -e "s/^.*= //p" | tr -d '\r')

回答by Amir Afghani

Try this:

尝试这个：

SUFFIX=";0"
DATA="${DATA}${SUFFIX}"

回答by Gilles Quenot

With awk, it will be more reliable and cleaner I guess :

使用awk，我猜它会更可靠和更干净：

$ awk '=="overall"{print "Working code\nData: "  "\n"  ";0"}' file.txt
Working code
Data: 324.88
324.88;0