Question

I have a matrix class defined this way:

template<int M, int N, typename T>
class Matrix
{
 typedef Matrix<M, N, T> MTYPE;
 /*...*/
};

I have to implement the matrix multiplication but I do not know how to do the operator overriding..

Something like

MTYPE operator *(MTYPE& m) { /*...*/ }

Would accept only a N*M matrix. So how can I overcome this problem?

Answer 1

As has been pointed out in a comment, *= doesn’t make sense for non-square matrices.

For the general case,

template<int M, int N, typename T>
class Matrix
{
    typedef Matrix<M, N, T> MTYPE;
    /*...*/
public:
    template<int L>
    Matrix<M,L,T> operator*(const Matrix<N,L,T>& second) const
    {
       Matrix<M,L,T> result;
       for(...)
           for(...)
               for(...)
                   // ...
       return result;
    }
};

Or, if you prefer, use a free function operator* with two parameters (and template arguments M,N,L, and T), and make it a friend of your matrix class.