pytransform3d.transformations.check_dual_quaternion

pytransform3d.transformations.check_dual_quaternion(dq, unit=True)[source]

Input validation of dual quaternion representation.

See http://web.cs.iastate.edu/~cs577/handouts/dual-quaternion.pdf

A dual quaternion is defined as

\sigma = p + \epsilon q,

where p and q are both quaternions and \epsilon is the dual unit with \epsilon^2 = 0. The first quaternion is also called the real part and the second quaternion is called the dual part.

Parameters
dqarray-like, shape (8,)

Dual quaternion to represent transform: (pw, px, py, pz, qw, qx, qy, qz)

unitbool, optional (default: True)

Normalize the dual quaternion so that it is a unit dual quaternion. A unit dual quaternion has the properties p_w^2 + p_x^2 + p_y^2 + p_z^2 = 1 and p_w q_w + p_x q_x + p_y q_y + p_z q_z = 0.

Returns
dqarray, shape (8,)

Unit dual quaternion to represent transform: (pw, px, py, pz, qw, qx, qy, qz)

Raises
ValueError

If input is invalid

Examples using pytransform3d.transformations.check_dual_quaternion