quaternion_multiply

compas.geometry.quaternion_multiply(r, q)

Multiplies two quaternions.

Parameters:

r[float, float, float, float] | compas.geometry.Quaternion

Quaternion or sequence of four floats [w, x, y, z].

q[float, float, float, float] | compas.geometry.Quaternion

Quaternion or sequence of four floats [w, x, y, z].

Returns:

[float, float, float, float]

Quaternion $p=rq$ as a list of four real values [pw, px, py, pz].

See also

quaternion_is_unit

quaternion_norm

quaternion_unitize

quaternion_canonize

quaternion_conjugate

Notes

Multiplication of two quaternions $p=rq$ can be interpreted as applying rotation $r$ to an orientation $q$, provided that both $r$ and $q$ are unit-length. The result is also unit-length. Multiplication of quaternions is not commutative!

References

• Quaternion: http://mathworld.wolfram.com/Quaternion.html