Hi, let's suppose we have tab-separated data like that in the lines after the __DATA__ token and we want to swap columns two and three: 

use strict;
use warnings;

while (<DATA>) {    # go through data line by line
    chomp;          # don't forget to remove newline character
    my @fields = split /\t+/;
    print join "\t",           # join fields with tab
          @fields[ 0, 2, 1 ],  # select fields using array slice
          "\n";
}

__DATA__
Col1    Col2    Col3
a       b       c
1       2       3

[download]

To work with files, just

and then run the program like this: 

$ perl script.pl *.dat

[download]

Excellence is an art won by training and habituation: we do not act rightly because we have virtue or excellence, but we rather have these because we have acted rightly. -- Will Durant

In reply to Re: Rearranging columns in multiple text files by reisinge
in thread Rearranging columns in multiple text files by MVRS

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