Hmmm...still struggling with this one and getting an error :

Can't use an undefined value as an ARRAY reference at combine_primer_lists.pl line 42, <INFILE> line 1.

relating to this line:

    } @{$dataset->{$col[0]}})[0]->[2];

Could you explain what this line is doing?

 #!/usr/bin/perl
#22/06/2011

use strict;
use warnings;
use File::Slurp;
use Data::Dumper;
my @data;
my @col;
my @dataset;
my $a;
my $b;
my @fields;
my %out;

open INFILE, "<Primer-Rev1" or die $!;
open my $outfh, '>', "outputfile.txt" or die $!;

    for my $nr (1..2) {
     for my $line (read_file('Primer-For'.$nr)) {
      my @col = split(/\t/,$line);
      push @{$data[$nr - 1]->{shift(@col)}},\@col;
     }
    }


while (<INFILE>){

        @col = split(/\t+/, $_);
        chomp (@col);
         my ($header, $length, $tm, $sequence) = @col[0..3];

        # expecting file3 line in @col
        my @results = ($col[0],$col[3]);
        for my $dataset (@data) {
         push @results,(sort {
           my $diff_a = $col[2] - $a->[1];
           $diff_a *= -1 if $diff_a < 0;
           my $diff_b = $col[2] - $b->[1];
           $diff_b *= -1 if $diff_b < 0;
           $diff_a <=> $diff_b;
          } @{$dataset->{$col[0]}})[0]->[2];
        }
}

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In reply to Re^2: Combining 3 files by garyboyd
in thread Combining 3 files by garyboyd

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