%  ex_01_07_1.m :  習題 1.7

clear;
N=3;
M=3;
Mlag=3;
h = [3 2 1];
rh1=xcorr(h,Mlag,'biased');
rh1=N*rh1

M=4; 
Mlag=3;
x = [1 2 3 4];
h=[3 2 1];
rx1=xcorr(h,x);

t=[-3,-2,-1,0,1,2,3];
subplot(221);stem(t,rh1,'.');grid on;
subplot(222);stem(rx1,'.');grid on;