ex051100.m

stft(含:短时傅立叶变换 Gabor变换等)

% Chapter 05: Example 05.11: Circular shift graphical display
%
subplot(1,1,1)
% a) plot x((n+4))11
n = 0:10; x = 10*(0.8) .^ n;
n1 = -11:21; x1 = [zeros(1,11), x, zeros(1,11)];
subplot(2,2,1); stem(n1,x1); title('Original x(n)')
xlabel('n'); axis([-6,17,-1,11])
x2 = [x, x, x];
subplot(2,2,3); stem(n1,x2); title('Periodic extention')
xlabel('n'); axis([-6,17,-1,11])
x3 = [x2(4+1:33), x(1:4)];
subplot(2,2,2); stem(n1,x3); title('Periodic shift')
xlabel('n'); axis([-6,17,-1,11])
x4 = x3 .* [zeros(1,11), ones(1,11), zeros(1,11)];
subplot(2,2,4); stem(n1,x4); title('Circular shift')
xlabel('n'); axis([-6,17,-1,11])
pause;
%print -deps2 me0511a.eps
%
% b) plot x((n-3))15
n = 0:10; x = [10*(0.8) .^ n zeros(1,4)];
n1 = -15:29; x1 = [zeros(1,15), x, zeros(1,15)];
subplot(2,2,1); stem(n1,x1); title('Original x(n)')
xlabel('n'); axis([-9,25,-1,11])
x2 = [x, x, x];
subplot(2,2,3); stem(n1,x2); title('Periodic extention')
xlabel('n'); axis([-9,25,-1,11])
x3 = [x2(43:45),x2(1:42)];
subplot(2,2,2); stem(n1,x3); title('Periodic shift')
xlabel('n'); axis([-9,25,-1,11])
x4 = x3 .* [zeros(1,15), ones(1,15), zeros(1,15)];
subplot(2,2,4); stem(n1,x4); title('Circular shift')
xlabel('n'); axis([-9,25,-1,11])
pause;
%print -deps2 me0511b.eps
%