Sed replace character after every number

Question

I want to replace a character after every integer number with sed.

Example:

444 d should go: 444,d

EDIT: The answer of stribizhev helped me out to find a solution with sed (GNU sed) 4.2.2

sed -r 's/([0-9]+)./\\1,/g'

replaces an arbitary character after a number with a comma. The only problem is, that also a number at the end of the line creates an additional comma.

Answer 1

You can use capturing groups to do that:

sed 's/\(\d\+\)./\1,/g'

or (since with GNU sed you can avoid all the escaped parenthesis by using extended regular expressions)

sed -r 's/([0-9]+)./\1,/g'

Here is a demo showing what the regex does .

The [0-9]+ pattern matches an integer number (without decimals) even Iinside longer strings, even within longer words.