note
ikegami
<c>
use Scalar::Util qw( looks_like_number );
my $s = 123.45;
$s =~ s/\./,/ if looks_like_number($s);
</c>
<p>Works even better than setlocale because you are surely starting with the number in string form if you don't know whether a column contains a number or not.
852538
852544