matrix_from_axis_and_angle

compas.geometry.matrix_from_axis_and_angle(axis, angle, point=None)[source]

Calculates a rotation matrix from an rotation axis, an angle and an optional point of rotation.

Parameters:

axis[float, float, float]: Three numbers that represent the axis of rotation.
anglefloat: The rotation angle in radians.
point[float, float, float] | compas.geometry.Point, optional: A point to perform a rotation around an origin other than [0, 0, 0].

Returns:

list[list[float]]: A 4x4 transformation matrix representing a rotation.

Notes

The rotation is based on the right hand rule, i.e. anti-clockwise if the axis of rotation points towards the observer.

Examples

>>> axis1 = normalize_vector([-0.043, -0.254, 0.617])
>>> angle1 = 0.1
>>> R = matrix_from_axis_and_angle(axis1, angle1)
>>> axis2, angle2 = axis_and_angle_from_matrix(R)
>>> allclose(axis1, axis2)
True
>>> allclose([angle1], [angle2])
True