undef = <$trf> for 1 .. 4;

        my %hash = (); #initiate empty hash

        while( my $line=<$trf>)
            {
            chomp $line;
            my @line=split("\t",$line);


##</code><code>##

        my %hash = (); #initiate empty hash

        while ( my $line = <$trf> )
            {
            next if $. < 5; # skip first four lines
            chomp $line;
            my @line = split /\t/, $line;