Hi monks

I'm a relative Perl novice and am trying to write a piece of code which will parse information from a file in this format:

Name(tab)Signal(tab)Present or Absent (P or A) call

Basically it does this by incremeting present or absent counts in anonymous arrays existing as the values in a DBM hash. It then prints the present/absent calls out to two files.

The problem is that the hash seems to basically disappear when I exit the <while> loop which parses the input file and my two output files remain empty.

I'm stumped - any help would be sincerely appreciated.

Example input (1 present and 1 absent call):

sequence1\t7\tP\n

sequence2\t1\tA\n

Code:

#!/usr/bin/perl

use warnings;

$input = "infile";
$background = "2";

open (INPUT, $input) or die "Cannot open infile!$!";

dbmopen (%PAHASH, "crDB", 0777) or die "Cannot open DBM file!$!";

while (<INPUT>) {

  next if (/^Gene/) || (/^AFFX/) || (/^2000/);

  chomp (@linearray = split "\t", $_);
  $name = shift @linearray;
  $signal = shift @linearray;
  $affycall = shift @linearray;
  #$name =~ s/_.{2,4}$//;
  if ($affycall eq "P" && $signal>$background) {
    $$PAHASH{$name}[0]++;
    }
  else {
    $$PAHASH{$name}[1]++;
    }
}

open (PRESENT, ">present");
open (ABSENT, ">absent");

foreach $key (keys %PAHASH) {
  if (defined $$PAHASH{$key}[0]) {
    print PRESENT "$key\t($$PAHASH{$key}[0] present calls)";
    }
  else {
    print ABSENT "$key\t($$PAHASH{$key}[1] absent calls)\n";
    }
}
dbmclose %PAHASH;

exit;
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