Merge multiple consecutive lines
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Input file:
$ cat infile.txt
aid=33
pw=3
nn=90
aid=32
pw=30
nn=70
aid=56
pw=3
nn=93
Required:
Combine or merge every three consecutive lines of the above file so that the output becomes:
aid=33,pw=3,nn=90
aid=32,pw=30,nn=70
aid=56,pw=3,nn=93
Awk solution: If line number is divisible by 3 then put a new line(\n) else put a comma(,) i.e.
$ awk '{printf("%s%s", $0, (NR%3 ? "," : "\n"))}' infile.txt
aid=33,pw=3,nn=90
aid=32,pw=30,nn=70
aid=56,pw=3,nn=93
Another way using Awk:
$ awk 'NR%3{printf $0",";next;}1' infile.txt
aid=33,pw=3,nn=90
aid=32,pw=30,nn=70
aid=56,pw=3,nn=93
Using UNIX paste command:
$ paste -d"," - - - < infile.txt
aid=33,pw=3,nn=90
aid=32,pw=30,nn=70
aid=56,pw=3,nn=93
A bash command line solution:
$ while read line1; do read line2; read line3; echo "$line1,$line2,$line3"; done < infile.txt
aid=33,pw=3,nn=90
aid=32,pw=30,nn=70
aid=56,pw=3,nn=93
