% fir.m - sample processing algorithm for FIR filter.%% [y, w] = fir(M, h, w, x)%% h = order-M filter (row vector)% w = filter state (row vector)% x = scalar input% y = scalar output% based on fir2.cfunction [y, w] = fir(M, h, w, x)w(1) = x;                          % read inputy = h * w';                        % compute outputw = delay(M, w);                   % update delay