kron

A = [1,2;3,4];
kron(A,A)
A.*.A
sparse(A).*.sparse(A)
A(1,1) = %i;
kron(A,A)

// With hypermatrices
// ------------------
b = hypermat([4 3 2], 1:24);

// row .*. hypermat
clc
a = 1:2, b
a.*.b

// hypermat .*. row
clc
b,a
b .*. a

// column .*. hypermat
clc
a = [1;2], b
a.*.b

// matrix .*. hypermat
clc
a = [-1 -2; 2 1], b
a.*.b

// hypermat .*. hypermat
clc
a = hypermat([1 2 2],[-1,-2, 1 2]), b
a.*.b