Create a special diagonal matrix

Question

I want to create a special diagonal matrix in MATLAB that uses [1 1] or any other array as main diagonal elements. Something like the following:

[1   1   0   0   0   0
 0   0   1   1   0   0
 0   0   0   0   1   1]

How can I do that without using any loop structures?

Answer 1

Let

v = [1 1];
n = 3;

• Using kron:

  result = kron(eye(n), v);
  

• Using blkdiag:

  vv = repmat({v}, 1, n);
  result = blkdiag(vv{:});