使用sed提取多个值

Question

So, I am trying to extract multiple values from a string using sed that are separated by ",".

Working Eg:

Input :
    echo "abc-de-aa-zzzz-1.2.3-4" | sed -E 's/(^([a-z]{3}-[a-z]{1,5}-[a-z]{1,5}-[a-z]{1,15})).*/\1/'

Output: 
     abc-de-aa-zzzz

Need help with the below expression:

Not Working Eg:

Input:
    echo "abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4" | sed -E 's/(^([a-z]{3}-[a-z]{1,5}-[a-z]{1,5}-[a-z]{1,15})).*/\1/'

 Current output:
      abc-de-aa-zzzz

 Correct output:
      abc-de-aa-zzzz,abc-de-aa-kkkk

 This one works as well:
      abc-de-aa-zzzz
      abc-de-aa-kkkk

Thanks,

Jason

Answer 1

Sample input:

echo $x
abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4

awk only solution:

 echo $x  |awk  'BEGIN{RS=",";FS=OFS="-"}{NF=4}1'
 abc-de-aa-zzzz
 abc-de-aa-kkkk

OR this, if you want output to be comma separated. (One extra comma at the end)

echo $x  |awk  'BEGIN{ORS=RS=",";FS=OFS="-"}{NF=4}1'
abc-de-aa-zzzz,abc-de-aa-kkkk,

dirty solution using tr and awk :

echo $x |tr ',' '\n' |awk -F'-' -v OFS='-' '{NF=4}1'
abc-de-aa-zzzz
abc-de-aa-kkkk

Answer 2

It can be done pure Bash shell parameter expansion techniques but it involves multi-levels of extraction (two) though without using any third partly Linux tools like awk or sed . You can run them directly on the command line.

# Read the input string into a bash array with a comma delimiter
$ IFS="," read -ra inputString <<< "abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4"

# For each of the individual strings, extract the sub-string from the end
# with de-limiter set as '-'
$ for eachString in "${inputString[@]}"; do tempString="${eachString%-*}"; \
       tempString="${tempString%-*}"; printf "%s\n" "$tempString"; done
abc-de-aa-zzzz
abc-de-aa-kkkk
$

Answer 3

One way is to delete only string not needed, in this case deletion pattern is - followed by 3 set of digits with . as delimiter and then a final sequence of digits

$ echo "abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4" | sed -E 's/-([0-9]+\.){2}[0-9]+-[0-9]+//g'
abc-de-aa-zzzz,abc-de-aa-kkkk

Alternate solutions: - extract what is required

Using grep and pcre

$ echo "abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4" | grep -oP '(^|,)\K([^-]+\-){3}[^-]+'
abc-de-aa-zzzz
abc-de-aa-kkkk

Using GNU sed

$ echo "abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4" | sed 's/,/\n/' | sed -E 's/^(([^-]+\-){3}[^-]+).*/\1/'
abc-de-aa-zzzz
abc-de-aa-kkkk

In case you need to combine the output as single line delimited by ,

$ echo "abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4" | grep -oP '(^|,)\K([^-]+\-){3}[^-]+' | paste -s -d,
abc-de-aa-zzzz,abc-de-aa-kkkk

Answer 4

With awk :

awk -F, '{while(++i<=NF){sub(/-[0-9].*/,"",$i);print $i}}'

Sample:

echo "abc-de-aa-zzzz-1.2.3-4,abc-de-aa-kkkk-1.2.5-4" | awk -F, '{while(++i<=NF){sub(/-[0-9].*/,"",$i);print $i}}'
abc-de-aa-zzzz
abc-de-aa-kkkk