c73.m

matlab例程MATLAB 6.x版的内建数据类型（Built-in data type）就有5种以上

w0=120*pi;
theta=[60 80 87]*(pi/180);
for m=1:length(theta)
	num=[1 0 w0^2];
	den=[1 2*w0*cos(theta(m)) w0^2];
	w=0:.5:1000; w=w';
	[mag,phase,w]=bode(num,den,w);
	plot(w,mag),hold on,axis([0 1000 0 1.1])
end