Hello I have this code for Game of life now I am getting an error in calculating the num_neighbors. Please help me fix it. Thank you

     mylife = round(rand(size_of_game,size_of_game));
  %mylife = [0 0 0 0 0;0 0 0 0 0;0 1 1 1 0;0 0 0 0 0 ;0 0 0 0 0 ];

%%%plot

while 1%for 11 = 1:1000
    axis([-size_of_game size_of_game -size_of_game size_of_game])
    cla;
    spy(mylife)
    grid on 
    %propagate
    newlife = mylife;
    for ii = 1:size_of_game
        si = ii-1;
        ei = ii+1;
        veci = si:ei;
        veci(veci==0)=size_of_game;
        veci(veci==size_of_game)=1;
        for jj = 1:size_of_game
            %%%This is overlap from each side
            sj = jj-1;
            ej = jj+1;
            vecj = sj:ej;
            vecj(vecj==0)=size_of_game;
            vecj(vecj==size_of_game+1)=1;
            num_neighbors =sum(sum(mylife(veci,vecj)))-mylife(ii,jj);
            if mylife(ii,jj)
                %Any live cell with fewer than 4 live neighbours dies
                if num_neighbors <= 4
                    newlife(ii,jj) = 0;
                end
                %Any live cell with four or more live neighbors lives on to
                %next generation
                if num_neighbors > 4
                    newlife(ii,jj) = 1;
                end
            end
        end
    end
    drawnow
    mylife=newlife;
end

Answer 1

[Aveek Podder]

Hi,

I think you are receiving an "Index exceeds matrix dimensions" error, that is due to the fact that the elements in vector 'veci' is exceeding the 'size_of_game'. This issue can be avoided by changing the roll back condition of 'veci'.

The rollback condition for 'veci' is given below:

 veci(veci==size_of_game+1)=1;