Use sed command with substring to replace

Question

I am looking to use the sed command to replace a substring value.

I have a file like this

UNIT56712423MP000000R0990

The records in this file are always of the same length.

I need to check if the 21st character is R, then replace characters 13-14 from MP to GH.

Is there a way I can achieve this through the sed command?

Thanks for your help.

Answer: Yes. Please, as a new user, take the [tour] and read [ask]. You won't get anyone here to do your homework for you if you don't even show a minimal amount of effort. — Ulrich Eckhardt, Apr 29 '19 at 15:01
If you have a problem with a regex, please show the regex so that we could help you fix it, — Wiktor Stribiżew, Apr 29 '19 at 15:35

score 0 · Answer 1 · answered May 01 '19 at 03:46

0

tried on gnu sed

sed -E '/^\w{20}R\w{4}$/s/^(.{12})../\1GH/' <<<UNIT56712423MP000000R0990

answered May 01 '19 at 03:46

1 Answers1