n = 100; % number of steps
P = zeros(n,1); %position(time) vector
P(1) = 0; % Starting value
for i=2:n    
  R = rand;
  if R < 0.5
    S = -1;
  elseif R > 0.5
     S = 1;
  end
  P(i) = S+P(i-1); 
end
plot(1:n,P)
ylabel('Position')
xlabel('Step Count')
title('1-D Random Walk')