MATLAB: How can i give rand function as an input to the given difference equation

Question

n=10
x(n)=randn(n,1)
y(n)=2.5*x(n)+ x(n-1)

The x(n)should be given as input to the y(n) but when i tried doing that x(n) it is giving me the following error.

???  In an assignment  A(I) = B, the number of elements in B and
 I must be the same.
Error in ==> Untitled at 5
x(n)=randn(n,1).

But without using x(n) i cannot give the input to the y(n).

Kindly provide me a solution.

Answer 1

You need a loop:

n = 10;
x = randn(n,1);
for k1 = 2:n
    y(k1) = 2.5*x(k1) + x(k1-1);
end
figure(1)
plot(x, y, '-o')
grid