% ca_1D.m  -  one-dimnesional CA with 2 states and 2 neighbors
% Feb.9, 2003                   
%                               SG

clear all
close all

% PARAMETERS

RULE = 54;          % rule #
cells = 100;         % number of cells
T = 100;             % number of iterations


% INITIAL STATE
init = round(rand(1,cells));     % random initial states

init = zeros(1,cells);           % single red in the middle
init(cells/2) = 1;

% USEFUL

rule = bitget(RULE,8:-1:1);         % convert RULE to a 1x8 binary array
vec = [4 2 1];

X(1,:) = init;

tic
for t=1:T
    
    Y = X(t,:);

    d(2,:) = Y;
    d(1,:) = [Y(end) Y(1:(end-1))];
    d(3,:) = [Y(2:end) Y(1)];
   

    X(t+1,:) = rule(8-vec*d(:,:));

end
toc

z = zeros(size(X));
image(cat(3,X,z,z));

axis equal
axis tight
xlabel('space')
ylabel('time')
title(['Rule ', num2str(RULE)])