#!/usr/bin/perl
# Stephen Flitman - extract one or more columns of a table
# Released under GPLv2
# Usage: ... | xcol N M ...
# where N, M, ... are 0-based column indices, and columsn are split by
+ tabs
# if invoked without arguments, tells you what columns are present and
+ their indices, useful if there is a header row
use strict;
if (@ARGV) {
while (<STDIN>) {
chop;
my @fields=split(/\t/,$_);
for (my $i=0; $i<=$#ARGV; $i++) {
print $fields[$ARGV[$i]];
print "\t" if $i<$#ARGV;
}
print "\n";
}
} else {
my $line;
until ($line=~/\t/) { $line=<STDIN>; }
chop $line;
die "No lines to process" unless $line;
my $i=0;
for my $field (split(/\t/,$line)) {
printf "%3d: $field\n",$i++;
}
}
exit;
In reply to xcol
by sflitman
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