Your three-deep loop could be written, 

my @array = (undef) x $size[0];
$_ = [ map { [(0) x $size[2]] } (undef) x $size[1] ] for @array;

[download]
Inside the map block is what happens in your deepest loop level. That is a reference to an array of $size[2] zeros. The list map acts on is bogus. Any list of $size[1] items would do there because the data in that list is never touched or remembered. It's only there to make $size[1] different copies of the inner array. A reference is taken to the whole map expression to make the top level data in @array.

Setting 3d array elements is easier than you think. Just say, 

$array[$foo][$bar][$baz] = $quux
    if $foo >= -$size[0] and $foo < $size[0]
        and $bar >= -$size[1] and $bar < $size[1]
        and $baz >= -$size[2] and $baz < $size[2];

[download]
If you don't care about checking index range, all that logic can go.

blokhead's lvalue sub for fetch and store is an elegant approach.

After Compline,
Zaxo

In reply to Re: N-Dimensional Arrays on the fly by Zaxo
in thread N-Dimensional Arrays on the fly by qumsieh

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.