Recent discussion of Pascal's triangle reminded me of a cool 1-D Cellular Automata and Wolfram's famous Rule 30.

Try $rule = 18, 22, 30, 45, 54, 110, or 150 for some snazzy Pascal's Triangle variations.

RuleFoo

update: Also rules 122, 126, 129, 146, 151 

#!/usr/bin/perl

   use strict;

   my $rule = shift || 30;
   my $wide = shift || 80;
   my $high = shift || 60;

   my $binary = reverse(substr(sprintf("%8.8b", $rule), -8, 8));
   $binary =~ tr/01/ */;
   #print "$binary\n";

   my (%rules, $key, $i);

   for ($i = 7; $i >= 0; $i--) {
      $key = sprintf("%3.3b", $i);
      $key =~ tr/01/ */;
      $rules{$key} = substr($binary, $i, 1);
      #print "$key $rules{$key}\n";
   }

   my ($str, @chs);

   for (1..$wide) {
      if (rand(2) < 1) { $str .= ' '; }
      else             { $str .= '*'; }
   }

   for (1..$high) {
      @chs = split('', $str);
      print "$str\n";
      $str = '';
      for ($i = 0; $i < $wide; $i++) {
         $key = "$chs[$i-1]$chs[$i]$chs[($i+1)%@chs]";
         $str .= $rules{$key};
      }
   }

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In reply to 1-D Cellular Automata by YuckFoo

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