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deepblue_86
Asked: 2016-12-01 00:19:23 +0800 CST

merging particular text files in different directories

  • 772

I have 6 directories. Each directory includes 8 text files. These text files share the same prefix. I need to combine these text files as follows;

Assume, first text file in directory_1 contains files containing the text abc_1, directory_2 contains files with the text abc_2 and so on. Merged text file for the first text files needs to be in this form:

abc_1
abc_2
abc_3
..
abc_6

The second, third... and eighth text files also need to be combined with the same rule.

command-line

2 Answers

  1. An implicit method (can fail if unrelated files with filename ending with _ and a number are in the same directory) which names each merged file according to the file number:

    DIRS_BASE=directory_
for ((FNUM=1; FNUM<9; FNUM++)); do
    cat ${DIRS_BASE}[1-6]/*_${FNUM} > merged_${FNUM}
done

    An explicit method (safer) using a list of prefixes, which names each merged file according to the file number:

    DIRS_BASE=directory_
PLIST=(abc def ghi jkl mno pqr)
NDIRS=${#PLIST[@]}
for ((FNUM=1; FNUM<9; FNUM++)); do
    PLIST_NUM=(${PLIST[@]/%/_$FNUM})
    cat ${PLIST_NUM[@]/#/$DIRS_BASE[1-$NDIRS]/} > merged_${FNUM}
done
    • 3
  2. Best Answer

    Your files must be sortable, so assuming the names of the files in each directory end with a number from 1 to 8, such as foo1, foo2... in one directory and bar1, bar2... in another and so on, you could use cat and a for loop to concatenate them:

    for j in {1..8}; do cat directory_{1..6}/*$j > newfile$j; done

    (no need to "quote" a variable we know is a single digit) This will print, in, for example, newfile1, the contents of

    directory_1/foo1
directory_2/bar1
directory_3/baz1
...

    whatever those contents are, and in newfile2 the contents of directory_1/foo2, diectory_2/bar2 etc

    • 1