Isn't this so much easier to understand?

#!/usr/bin/perl
use warnings;
use strict;

my @in = ([1,2,3,4,'a','b','c'],
          ['z','y','x','w',9,8,7],
          ['e','f','g','h',5,4,6],
          );
my @out;

for my $y (0..(@in-1)) {
    for my $x (0..(@{$in[$y]}-1)) {
        $out[$x][$y] = $in[$y][$x];
    }
}
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No need to be a Perl geek to do this right! And think of the ease of maintenance!

for my $y (0..(@in-1)) {
    for my $x (0..(@{$in[$y]}-1)) {
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I'm puzzled as to why you do the subtractions to find the upper bound of the arrays rather than use the $#array that Perl provides.

for my $y ( 0 .. $#in ) {
    for my $x ( 0 .. $#{$in[$y]} ) {
[download]

Cheers,

JohnGG

My original did, but the second loop definition was looking like line noise and I was demonstrating the practice to a novice. So I opted for the more verbose, and less obtuse example.