push will also work without explicitly defining your sub-arrays and getting references to them, as in the following:

use strict;
use warnings;
use Data::Dumper;

my @letter_array = ();
my @letters = ('A' .. 'Z');

foreach my $letter (@letters) {
    my $selection = int rand 4;
    push @{$letter_array[$selection]}, $letter;
}

print Dumper(\@letter_array);

[download]

Will produce (in at least one case):

$VAR1 = [
          [
            'F',
            'K',
            'O',
            'T',
            'U',
            'V',
            'X'
          ],
          [
            'B',
            'I',
            'Q',
            'W'
          ],
          [
            'A',
            'D',
            'E',
            'H',
            'J',
            'L',
            'M',
            'P',
            'S',
            'Z'
          ],
          [
            'C',
            'G',
            'N',
            'R',
            'Y'
          ]
        ];

[download]

This works because of autovivification. Check perlref in your docs if this fifty-pfenning term piques your interest.

Hanlon's Razor - "Never attribute to malice that which can be adequately explained by stupidity"

In reply to Re: creating arrays of arrays by Art_XIV
in thread creating arrays of arrays by Anonymous Monk

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.