function dx = fischer(t,x)

dx = zeros(length(x),1);
d = 1;
dx(1) = x(1)*(1-x(1)) + (-x(1)+x(2))/d^2; 

for i = 1:(length(x)-2)
    dx(i+1) = x(i+1)*(1-x(i+1))+(x(i)-2*x(i+1)+x(i+2))/d^2;
end

dx(end) = x(end)*(1-x(end)) + (x(end-1)-x(end))/d^2;