function [ok] = blkbidiag_mul_ok()
ok = true;
% -------------------------------------------------------------
% You can change these parameters
m = 2;
n = 3;
N = 4;
p = 3;
% -------------------------------------------------------------
% Define the problem
rand('seed', 123);
v = rand(n * N, 3);
rand('seed', 123);
a = rand(n, n, N);
r = rand(n * N, m);
Hdia = rand(n, n, N);
Hlow = rand(n, n, N);
Hcheck = zeros(n*N);
blk_n = 1 : n;
for k = 1 : N
Hcheck(blk_n, blk_n) = Hdia(:,:, k);
blk_n = blk_n + n;
end
blk_n = 1:n;
for k = 2:N;
blk_minus = blk_n;
blk_n = blk_n + n;
Hcheck(blk_n, blk_minus) = Hlow(:,:, k);
end
% -------------------------------------
H = ckbs_blkbidiag_mul(Hdia, Hlow, eye(n*N));
% -------------------------------------
check = H - Hcheck;
ok = ok & ( max(max(abs(check))) < 1e-10 );
return
end