From: vanjac12@... (Van Jacques)
Date: 2003-12-03T06:57:07+09:00
Subject: Re: New to ruby--trouble with initializing arrays

"Robert Klemme" <bob.news@gmx.net> wrote in message news:<bqffva$22171v$1@ID-52924.news.uni-berlin.de>...
> >
> > Does this help:
> 
> Slightly improved to tackle the borders.
> 
> class Board
>   def initialize(size=8)
>     @size = 8
>     @values = Array.new( size * size, 0 )
>   end
> 
>   def [](x,y)
>     @values[pos(x,y)]=v
>   end
> 
>   def []=(x,y,v)
>     @values[pos(x,y)]=v
>   end
> 
>   protected
>   def pos(x,y)
>     ( x % @size ) * @size + ( y % @size )
>   end
> end
> 
> > board = Board.new
> > tmp = board.dup
> > # manipulate tmp
> > board = tmp
> 
>     robert

This is much more sophiscated than my program (with help from another
poster in a similar thread here in comp.lang.ruby), but I used the 

row % size 

method for dealing with the edges also. The following initial configuration
goes a long time before oscillating (I think), and I recommend running it
for anyone who is interested.

As a beginner, I'm not used to defining my own classes or def statements,
but that will come with time--I hope :-)
===========

NN = 20 ; N = NN - 1
n_steps = 100

tos = Array.new
tng = Array.new

0.upto(N) { |row|
  tos[row] = Array.new(NN, 0)
  tng[row] = Array.new(NN, 0)
}


tos[4][4] = tos[5][6] = tos[6][3] = tos[6][4] = 1
tos[6][7] = tos[6][8] = tos[6][9] = 1

0.upto(N) do |row|
  print tos[row], "\n"
end
puts

1.upto(n_steps) do |generation|
  0.upto(N) do |row|
    0.upto(N) do |column|
      neighbors = 0
      -1.upto(1) do |row_offset|
        -1.upto(1) do |column_offset|
          unless row_offset == 0 and column_offset == 0
            i = (row+row_offset) % NN
            j = (column+column_offset) % NN
            neighbors += tos[i][j]
          end
        end
      end
      if tos[row][column] == 0
        tng[row][column] = (neighbors == 3) ? 1 : 0
      else
        tng[row][column] = (neighbors == 2 or neighbors == 3) ? 1 : 0
      end
    end
  end

  0.upto(N) do |row|
    0.upto(N) do |column| 
    tos[row][column] = tng[row][column]
    end
    print tos[row], "\n"
  end
  puts
  puts generation
  puts

  0.upto(N) do |row|
    0.upto(N) do |column|
      print (tos[row][column] == 0 ? ' ' : 'X')
    end
 puts
 end
end
#done