py3dframe.Frame.get_rotation_vector

Frame.get_rotation_vector(*, convention=None, degrees=False)

Access the rotation vector representation of the rotation between the parent frame and this frame in a specific convention.

The rotation vector describes the rotation by a single rotation about a fixed axis. The direction of the axis is given by the direction of the vector, and the magnitude of the vector is given by the angle of rotation.

See also

• attribute parent to get or set the parent frame.

• attribute convention to get or set the convention of the frame.

• attribute rotation_vector to get or set the rotation vector in the convention of the frame.

• method set_rotation_vector() to set the rotation vector in a specific convention.

• method get_global_rotation_vector() to get the rotation vector between the global frame and this frame.

Parameters:

• convention (Optional[int], optional) – Integer in [0, 7] selecting the convention. Defaults to the frame’s own convention.

• degrees (bool, optional) – If True, the rotation vector is returned in degrees. Default is False (radians).

Returns:

The rotation vector between the parent frame and this frame in the given convention with shape (3,).

Return type:

numpy.ndarray

Examples

Lets create a frame from its axes and origin with the default convention 0.

import numpy
from py3dframe import Frame

origin = numpy.array([-1, -2, -3])
x_axis = numpy.array([1, 1, 0]) / numpy.sqrt(2)
y_axis = numpy.array([-1, 1, 0]) / numpy.sqrt(2)
z_axis = numpy.array([0, 0, 1])

parent = ... # Define the parent frame if needed, otherwise parent=None to use the canonical frame.

frame = Frame.from_axes(origin=origin, x_axis=x_axis, y_axis=y_axis, z_axis=z_axis, convention=0, parent=parent)

If an application using an other convention required the rotation vector in the convention 4 in degrees, you can access the rotation vector in this convention with the get_rotation_vector() method.

rotation_vector_convention_4 = frame.get_rotation_vector(convention=4, degrees=True)