+ return m;
+}
+
+template<typename T, unsigned M, unsigned N>
+template<unsigned P, unsigned Q>
+inline Matrix<T, P, Q> Matrix<T, M, N>::block(unsigned y, unsigned x) const
+{
+ Matrix<T, P, Q> r;
+ for(unsigned j=0; j<P; ++j)
+ for(unsigned i=0; i<Q; ++i)
+ r(j, i) = element(y+j, x+i);
+ return r;