The sort function allows you to define your own sorting criteria, as an expression, a block of code or a subroutine.

You can split your records into three fields with something like split(/[\s,]+/). Then all you have to do is decide how to compare the fields.

You can use a lexical comparison (cmp) for the first field and a numeric comparison (<=>) for the second. These operators are described in perlop.

The third field is more challenging and how to proceed depends on details that are not clear to me. You say "each new X value" but not the context in which the value is "new". Are you concerned with the order in which they appear in the input file or the order they appear after sorting the first two fields or something else?

In reply to Re: Sort then conditionally sort by ig
in thread Sort then conditionally sort by lukez

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.