#!perl use warnings; use strict; use List::Util "max"; use Math::Complex; # what for? my $n = int($ARGV[-1] || 5); my($i, $j, $k, $x, $y, @l, @a, @v, @r, $wd, $fmt); for $i (0 .. $n - 1) { $x = $i - ($n - 1)/2; for $j (0 .. $n - 1) { $y = $j - ($n - 1)/2; $k = $i * $n + $j; $l[$k] = -max(abs($x), abs($y)); $a[$k] = -arg(cplx(1, -1) * cplx($x, $y)); } } @v = sort { $l[$a] <=> $l[$b] || $a[$a] <=> $a[$b] } 0 .. $n**2 - 1; @r[@v] = 1 .. $n**2; $wd = length($n**2); $fmt = join(" ", ("%${wd}d") x $n) . "\n"; for $i (0 .. $n - 1) { printf $fmt, @r[$i * $n .. $i * $n + $n - 1]; } __END__