windowed.m

经典《信号与系统》教程的matlab例程,对深入理解信号与系统相关概念有很大帮助

clear
n=-100:100;
a=10;
x=sin(0.2*pi*(n-a)+eps)./(0.2*pi*(n-a)+eps);

RN=u(n)-u(n-2*a-1);
subplot(311)
stem(n,x,'.')
axis([-30,50,-0.4,1.2])
subplot(312)
stem(n,RN,'.')
axis([-30,50,-0.4,1.2])
subplot(313)
y=x.*RN;
stem(n,y,'.')
axis([-30,50,-0.4,1.2])