while (@filename) { my $i; $file=shift @filename; use Cwd 'chdir'; chdir "./data"; open (FILE, "$file") or die; while () { next while $i++ <= 14; (my $id, undef, undef, my $signal, undef, undef)=split(/\t/); push @{$outputdata{$id}}, $signal; } close (FILE); } #### for $id (keys %outputdata) { print "$id:\t",(join("\t",@{$outputdata{$id}})),"\n"; }