I use this routine that I slightly changed from one posted here long ago, I think by Vroom, that I cannot find now in the site. It seems to work on those tests.

#!/usr/bin/perl -wl

use strict;

my @nums = qw(
              0e0
              0
              +0
              -0
              1.
              0.14
              .14
              1.24e5
              24e5
              -24e-5
              2.3.
              2.3.4
              1..2
             );

for (@nums) {
   print "ok: ", $_ if is_a_number($_);
}



###############
sub is_a_number {
###############

    my $var = $_[0];
             
    $var =~ s/^\s+//;
    $var =~ s/\s+$//;
    if ($var =~ /^([+-]?)(\d+\.|\.\d+|\d+)\d*([Ee]([+-]?\d+))?$/) {
        return(1) 
    } else { 
      return(0)
    }
}
[download]

Regards, Roberto

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.