[Vala] Quaternions

[Yu Feng <rainwoodman gmail com>]

If I remember correctly, the inverse of a quaternion (w, x, y, z) is
then defined as

(w, x, y, z)^-1 = (w, -x, -y, -z)

With the inverse defined, the quotient is defined as q/p = q * p^(-1)

In that sense (0, 0, 0, 1)/(0, 1, 0, 0) = (0, 0, 0, 1) * (0, -1, 0, 0)
which is well-defined.


Yu



On Thu, 2009-03-26 at 23:24 +0000, Maciej Piechotka wrote:
> William Swanson wrote:
>
> > --- Quaternions ---
> > Quaternions are complex numbers generalized into four dimensions. As
> > with complex numbers, all four basic operators  (+ - * /) are
> > well-defined. Quaternions are used to represent rotations in 3D, among
> > other things.
>
> Nearly. Quaternions doesn't have defined division as:
>
>  i * j = k
> -j * i = k
>
> k/i = j or -j?
>
> Regards