9-1.m

matlab要求编写函数

n=[0:6];
x=[1,-2,4,6,-5,8,10];
[x2,n2]=sigshift(x,n,-2)
[x3,n3]=sigshift(x,n,4)
[x4,n4]=sigadd(3*x2,n2,x3,n3)
[x1,n1]=sigadd(x4,n4,-2*x,n)
stem(n1,x1)