Without even trying to understand what was required, a lot is already possible with DBD::CSV.

$ cat pm1072615.csv
Month,Zone,Replicate,SpeciesA,SpeciesB,SpeciesC
Sept,1,1,5,10,15
Sept,1,2,0,5,10
Sept,1,3,5,0,5
Sept,2,1,5,5,5
Sept,2,2,10,15,10
Sept,2,3,0,0,5
$ cat pm1072615.pl
#!/usr/bin/perl

use 5.14.2;
use warnings;

use DBI;

my $dbh = DBI->connect ("dbi:CSV:", undef, undef, {
    f_ext       => ".csv/r",
    });

my $sth = $dbh->prepare (qq;
    select month, zone, replicate, avg (speciesa)
    from   pm1072615
    group  by month,zone, replicate;
    );
$sth->execute;
while (my $row = $sth->fetch) {
    printf "%-5s %3d %3d %8.5f\n", @$row;
    }
$ perl pm1072615.pl
Sept    2   1  5.00000
Sept    2   2 10.00000
Sept    1   1  5.00000
Sept    1   3  5.00000
Use of uninitialized value in printf at pm1072615.pl line 19.
Sept    1   2  0.00000
Use of uninitialized value in printf at pm1072615.pl line 19.
Sept    2   3  0.00000
$

[download]

Enjoy, Have FUN! H.Merijn

In reply to Re^4: Descriptive Stats from .csv file by Tux
in thread Descriptive Stats from .csv file by korsmo

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.