Oh okay, apologies for the buffoonery on my part.

The script seems to be working fine now, I added another next line: next if /^(\s\s-\d)/ && $1 > $limit;, because without it, it doesn't recognise regular Real numbers like -2, -5 etc.

The script:

#!/usr/bin/perl 
use strict;
use warnings;
use Regexp::Common qw /number/;


print "Enter limit: ";
chomp( my $limit = <STDIN> );
#$limit = abs($limit);

open my $IN, '<', "xt_spacer_results.hairpin" or die $!;
open my $SIFTED, '>', "new_xt_spacer_results.hairpin" or die $!;

while (<$IN>){
    next if /^None/;
    next if /^($RE{num}{real})/ && $1 > $limit;
    next if /^(\s\s-\d)/ && $1 > $limit;
    print $SIFTED $_;
}

close $IN;
close $SIFTED;

[download]

Haukex, you are a legend, thanks.

In reply to Re^10: Easiest way to filter a file based on user input by Peter Keystrokes
in thread Easiest way to filter a file based on user input by Peter Keystrokes

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