Kronecker product for large matrices

Question

I am looking for an effficient way of computing the Kronecker product of two large matrices. I have tried using the method kronecker() as follows:

Answer 1

If you are computing kron(I,A)*v where v is a vector you can do this using vec(A*V) where V reshapes v into a matrix. This uses the more general rule that vec(ABC)=kron(C',A)*vec(B). This avoids forming the Kronecker product and uses far less operations to perform the computation.

Note that V may need to be transposed depending on how matrix storage is handled (columns versus rows).