Compute the product of two polynomial matrices
Mtxprod1(Mtx, sMtx, p, P)
The coefficient matrix of a regular polynomial matrix
The coefficient matrix of a seasonal polynomial matrix
Degree of the regular polynomial matrix. p is less than P.
Degree of the seasonal polynomial matrix
Coefficient matrix of the product. The product matrix is in the form sAR * reg-AR, etc.
This polynomial product is used in seasonal VARMA modeling to check the multiplicative nature between the regular and seasonal polynomial matrices