Quaternions.jl

A Julia module with quaternion, octonion and dual-quaternion functionality

Quaternions are best known for their suitability as representations of 3D rotational orientation. They can also be viewed as an extension of complex numbers.

Implemented functions are:

+-*/^
real
imag  (a vector)
conj
abs
abs2
exp
log
normalize
normalizea  (return normalized quaternion and absolute value as a pair)
angleaxis  (taken as an orientation, return the angle and axis (3 vector) as a tuple)
angle
axis
exp
log
sin
cos
sqrt
linpol  (interpolate between 2 normalized quaternions)
rand
randn

Dual quaternions are an extension, combining quaternions with dual numbers. On top of just orientation, they can represent all rigid transformations.

There are two conjugation concepts here

conj  (quaternion conjugation)
dconj (dual conjugation)

further implemented here:

Q0  (the 'real' quaternion)
Qe  ( the 'dual' part)
+-*/^
abs
abs2
normalize
normalizea
angleaxis
angle
axis
exp
log
sqrt
rand

Octonions form the logical next step on the Complex-Quaternion path. They play a role, for instance, in the mathematical foundation of String theory.

+-*/^
real
imag  (a vector)
conj
abs
abs2
exp
log
normalize
normalizea  (return normalized octonion and absolute value as a tuple)
exp
log
sqrt
rand
randn