foreach $txtfile (glob("*.TXT")) {
   print $txtfile;
   print "\n";
   open FILE, "$txtfile";
   open NEWFILE, ">$txtfile.tmp";
   while (<FILE>){
      $_ =~ s/\n/ 1.0\n/ if $. = 1;
      print NEWFILE $_;
   }
   close FILE;
   close NEWFILE;
}