Sed match pattern N times

sedtext processing

I want to split a file into chunks with 2 words each.

$cat tmp
word1 word2 word3 word4 word5 word6 word7
$sed -e 's/word. word. /&\n/g' tmp
word1 word2 
word3 word4 
word5 word6 
word7
$sed -e 's/word. \{2\}/&\n/g' tmp
word1 word2 word3 word4 word5 word6 word7

I expected the last command to give same result as the one before it. What is wrong?

Best Answer

Sorry, seems like I figured it out just after posting.

It needs to be

sed -e 's/\(word. \)\{2\}/&\n/g' tmp

Apparently the parentheses are needed to let sed apply {2} condition on the entire pattern word. and not just preceding space.

Related Solutions

Using sed, how to format one word per line, removing white space

You can use tr:

tr -s "[[:blank:]]" "\n" < file | grep .

The [:blank:] character class includes all horizontal whitespace. The -s squeezes or reduces multiple character occurrences to one.

The grep removes a blank line (if present).

Split text file into lines with fixed number of words

Assuming your definition of word is a sequence of non-blank characters separated by blanks, here's an awk solution for your single-line file

awk '{for (i=1; i<=NF; ++i)printf "%s%s", $i, i % 500? " ": "\n"}i % 500{print ""}' file

Best Answer

Related Solutions

Using sed, how to format one word per line, removing white space

Split text file into lines with fixed number of words

Related Question