ex0512.m

数字信号处理（机械工业出版社）的源码

t = (0:1/100:10-1/100);				    % Time vector
x = sin(2*pi*15*t) + sin(2*pi*40*t); 	% Signal
y = fft(x); 			            	% Compute DFT of x
m = abs(y); p = unwrap(angle(y)); 	    % Magnitude and phase
f = (0:length(y)-1)*99/length(y); 		% Frequency vector
subplot(211); plot(f,m); title('Magnitude'); set(gca,'Xtick',[15 40 60 85]);
subplot(212); plot(f,p*180/pi); title('Phase');
set(gca,'Xtick',[15 40 60 85]);