Eq, Num and Fractional instances for vectors and matrices.
These make writing code much more convenient, but also much more
dangerous; thus you have to import this module explicitely.
In the case of Vector instances, all operations are pointwise
(including multiplication and division), and scalars are implicitly
converted to vectors so that all components of the resulting vectors
are the equal to the given scalar. This gives a set of consistent
In the case of Matrices, multiplication is usual matrix multiplication,
division is not implemented, and scalars are converted to diagonal
abs and signum are implemented to be normalize and norm
(in the case of matrices, Frobenius norm).