function lms_eval(N, mu)

% lms_eval(N, mu)
% Example: lms_eval(1000, 0.01)

h = [0 0 0 1 0 0 0 0];
w = randn(1, length(h));

z_h = zeros(length(h)-1, 1);
z_w = zeros(length(h)-1, 1);

x = zeros(1, length(h));

e_last = 0;
p = 1.0;

for n=1:N,
	xs = 0.1*randn();
	p = 0.99*p + 0.01*xs*xs;
	x = [xs x(1:length(x)-1)];
	d = x*h';
	y = x*w';
	e = d - y;
	
	w = w + mu*e*x*(1/(0.001+p));
	
	e_last = 0.5*e_last + 0.5*e*e;
	_e(n) = e_last;
	_p(n) = p;
end
	
plot(1:N, _e, 1:N, _p); grid;
w=w'