find all minimum values in file with at least 100 lines

for ff in directory; do numLines=`wc -l $ff`; numLines=$(echo $numLines | sed 's/ .*//g'); min=$(sort -nrk 1 $ff | tail -1); if [ $numLines -gt 100 ]; then echo $min >> minValues; fi;done;

By: user1234
2013-09-23 04:04:52

What Others Think

Hmm... This could do with some tidying up. First, I'd replace `wc -l $ff` with $(wc -l $ff) It uses one more character, but $(...) can be nested and `...` cannot. It's tempting to fold the two numLine assignments: numLines=$(wc -l $ff | sed 's/ .*//g') but I'd prefer to use bash and get rid of sed: numLines=$(wc -l $ff) numLines=${numLines% *} To save time, it's better to check the file length FIRST. Currently, you sort all the small files, then ignore the result: [ $numLines -lt 100 ] && continue Now, you don't need the min variable any more: sort -nrk 1 $ff | tail -1 >> minValues Next, I'd change that sort line again. Currently, it writes to 'minValues' one line at a time. If you've got a LOT of files, it'd be more efficient to do: sort -nrk 1 $ff | tail -1 done >> minValues Finally, I'd quote the "$ff" just in case the filenames have whitespace in them. for ff in directory/*; do numLines=$(wc -l "$ff"); numLines=${numLines% *}; [ $numLines -lt 100 ] && continue; sort -nrk 1 "$ff" | tail -1; done >> minValues 188 characters down to 157 :-) Minimising it fully: for f in directory/*;do n=$(wc -l "$f");n=${n% *};[ $n -lt 100 ]&&continue;sort -nrk 1 "$f"|tail -1;done>>minValues 115 characters
flatcap · 375 weeks and 3 days ago
And... :-) Swap &&continue;sort for ||sort for f in directory/*;do n=$(wc -l "$f");n=${n% *};[ $n -lt 100 ]||sort -nrk 1 "$f"|tail -1;done>>minValues 106 characters
flatcap · 375 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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