use warnings; 
..
# in the block
no warnings qw(uninitialized);

##</code><code>##

sub skipblanks {
#    my @data = @_;
    # you probably want $x = shift || 0;
    my $x    = shift;
#    foreach $x (@data) {
        if ($x) {
            $x =~ s/,/\./g;
        }
        return $x;
#   }
}