上代码: % Pole-Zero IIR filter to Lattice-ladder structure filter b = [1, 2, 2, 1]; a = [1, 13/24, 5/8, 1/3]; [K, C] = dir2ladr(b, a) % To Check [delta, n] = impseq(0, 0, 7); format long; hdirect = filter(b, a, delta) hlattice = ladrfilt(K, C, delta) [b