function y = impL1(arg1,n)% y=impL1(ntf,n=10) % Compute the impulse response from the comparator% output to the comparator input for a NTF H.% n is the (optional) number of points (10).% % This function is useful when verifying the realization% of a NTF with a specified topology.if nargin<2    n=10;endif isobject(arg1) & strcmp(class(arg1),'zpk')    z = arg1.z{1};    p = arg1.p{1};elseif isstruct(arg1)    if any(strcmp(fieldnames(arg1),'zeros'))	z = arg1.zeros;    else	error('No zeros field in the NTF.')    end    if any(strcmp(fieldnames(arg1),'poles'))	p = arg1.poles;    else	error('No poles field in the NTF.')    endendlf_den = padr(poly(z),length(p)+1);lf_num = lf_den-poly(p);if any(imag([lf_num lf_den]))    % Complex loop filter    lfr_den = real( conv(lf_den,conj(lf_den)) );    lfr_num = conv(lf_num,conj(lf_den));    lf_i = tf( real(lfr_num), lfr_den, 1);    lf_q = tf( imag(lfr_num), lfr_den, 1);    y = impulse(lf_i,n) + 1i * impulse(lf_q,n);else    y = impulse(tf(lf_num,lf_den,1),n);end