n=0:0.1:10;
x=sin(10*n);
y=n.^2;
z=x.*y;
subplot(311);stem(x);hold on;plot(x,'r-');ylabel('輸入x');grid;
subplot(312);stem(y);hold on;plot(y,'r-');ylabel('窗口y');grid;
subplot(313);stem(z);hold on;plot(z,'r-');ylabel('輸出保留部分z');grid;
hold off;
figure;
subplot(311);plot(x,'r-');ylabel('輸入x');grid;
subplot(312);plot(y,'r-');ylabel('窗口y');grid;
pause;
subplot(313);plot(z,'r-');ylabel('輸出保留部分z');hold on;plot(y,'b-');hold on;plot(-y,'b-');grid;
hold off;