You didn't show us what should NOT be matched. As far as we know, m/./ might be all that's needed to match the correct non-empty line. Or maybe only lines that give exactly those numbers and no other possible numbers should be accepted. Or if negative numbers or decimal points or fractions might be encountered. We'll just have to guess something out of thin air. 
for (@filedata)
{
    next if not m/\d+\.\.\d+/;
    @spans = m/(\d+\.\.\d+)/g;
    print "@spans\n";
}

[download]

--
[ e d @ h a l l e y . c c ]

In reply to Re: Regular expressions and metacharacters by halley
in thread Regular expressions and metacharacters by Jaya

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • 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! —
  • 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:
    & &amp;
    < &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.