ex0302.asv

数字信号处理（机械工业出版社）的源码

% Chapter 3: Example 3.4:

%  DTFT of finite duration seq using mat-vec operation
% [0, pi] axis divided into 501 points.
%

n = -1:3; x = 1:5; k = 0:500;

[X,w] = dtft(x,n,k);          

X = x * (exp(-j*pi/500)) .^ (n'*k); % DTFT using matrix-vector product

magX = abs(X); angX = angle(X);

realX = real(X); imagX = imag(X);

subplot(2,2,1); plot(w/pi,magX); grid

xlabel('frequency in pi units'); title('Magnitude Part'); ylabel('Magnitude')

subplot(2,2,3); plot(w/pi,angX); grid

xlabel('frequency in pi units'); title('Angle Part'); ylabel('Radians')

subplot(2,2,2); plot(w/pi,realX); grid

xlabel('frequency in pi units'); title('Real Part'); ylabel('Real')

subplot(2,2,4); plot(w/pi,imagX); grid

xlabel('frequency in pi units'); title('Imaginary Part'); ylabel('Imaginary')

%print -deps ex030400.eps