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I want to insert thousand separator into a number sequence with sed and this ugly RE sed -e :a -e 's/\(.*[0-9]\)\(\([0-9]\{3\}\)\(,[0-9]\{3\}\)*\(\.[0-9]*\)\)/\1,\2/;ta' [filename].

Is there a more elegant solution?



One thing I omitted just now: the number may have a decimal point. Give an example:


I want the result after separating 123,456.7890

Thanks and best regards.

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up vote 5 down vote accepted

It's not using sed, but you could try something similar to this:

echo "10000" | xargs printf "%'d\n"

Or a solution using sed from here:

echo "2312341" | sed -r ':L;s=\b([0-9]+)([0-9]{3})\b=\1,\2=g;t L'

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Thanks in advance. The printf works fine. while the sed version seems cannot handle decimal point correctly. – Summer_More_More_Tea Feb 21 '12 at 14:09

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