calculus

Overview

rowan.calculus.derivative	Compute the instantaneous derivative of unit quaternions.
rowan.calculus.integrate	Integrate unit quaternions by angular velocity.

Details

This subpackage provides the ability to compute the derivative and integral of a quaternion.

rowan.calculus.derivative(q, v)

Compute the instantaneous derivative of unit quaternions.

Parameters:

• q ((..,4) np.array) – Array of quaternions.
• v ((..,3) np.array) – Array of angular velocities.

Returns:

Array of shape (…, 4) containing element-wise derivatives of q.

rowan.calculus.integrate(q, v, dt)

Integrate unit quaternions by angular velocity.

Parameters:

• q ((..,4) np.array) – Array of quaternions.
• v ((..,3) np.array) – Array of angular velocities.
• dt ((..) np.array) – Array of timesteps.

Returns:

Array of shape (…, 4) containing element-wise integrals of q.

Example::

q = np.array([1, 0, 0, 0]) v = np.array([0, 0, 1e-2]) v_next = integrate(q, v, 1)