Problem solving with Unix commands

Re:Problem solving with Unix commands by darrenf on Thursday February 14, 2019 @06:00AM (#19161016)

All the pipes and non-builtin commands (especially python!) look like overkill to me, I must say.

    for set in *_data.csv ; do
        num=${set/_*/}
        success=${set/data/A}
        if [ ! -e $success ] ; then echo $num ; fi
    done

ETA: likely specific to bash, since I have no experience with other shells except for dalliances with ksh and csh in the mid-90s.

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Re:Problem solving with Unix commands by phaemon on Thursday February 14, 2019 @07:27AM (#19161358)

Yup, I'd probably have gone with a `for` loop also. A bit shorter:

  for set in *_data.csv; do
    [[ -f "${set/data/A}" ]] || echo "${set%_data.csv}"
  done

Edit: though I just write it out like this for formatting on HN. In real life, that would just be a one-liner:

for set in *_data.csv; do [[ -f "${set/data/A}" ]] || echo "${set%_data.csv}"; done

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Re:Problem solving with Unix commands by hellabites on Thursday February 14, 2019 @06:39PM (#19167150)

Just because I like GNU parallel:

    parallel -kj1 'f="{}"; [[ -f "${f/data/A}" ]] || echo $f' ::: *_data.csv

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