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rotations

rot_matrix(angle_rad, axis=(0, 0, 1))

Generate rotation matrix about arbitary axis https://en.wikipedia.org/wiki/Rotation_matrix#Rotation_matrix_from_axis_and_angle

Source code in mmg_toolbox/utils/rotations.py 
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def rot_matrix(angle_rad: float, axis=(0, 0, 1)):
    """
    Generate rotation matrix about arbitary axis
    https://en.wikipedia.org/wiki/Rotation_matrix#Rotation_matrix_from_axis_and_angle
    """
    axis = norm_vector(axis)
    ux, uy, uz = axis
    c = np.cos(angle_rad)
    s = np.sin(angle_rad)
    c1 = 1 - c
    r = np.array([
        [
            (ux * ux * c1) + c,
            (uy * ux * c1) - uz * s,
            (uz * ux * c1) + uy * s
        ],
        [
            (ux * uy * c1) + uz * s,
            (uy * uy * c1) + c,
            (uz * uy * c1) - ux * s,
        ],
        [
            (ux * uz * c1) - uy * s,
            (uy * uz * c1) + ux * s,
            (uz * uz * c1) + c,
        ]
    ])
    return r

rotation_t_matrix(value=0.0, vector=(0, 0, 1), offset=(0, 0, 0))

Create 4x4 transformation matrix including a rotation

Source code in mmg_toolbox/utils/rotations.py 
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def rotation_t_matrix(value=0.0, vector=(0, 0, 1), offset=(0, 0, 0)):
    """
    Create 4x4 transformation matrix including a rotation
    """
    t = np.eye(4)
    t[:3, :3] = rot_matrix(angle_rad=value, axis=vector)
    t[:3, 3] = offset
    return t

translation_t_matrix(value=0.0, vector=(0, 0, 1), offset=(0, 0, 0))

Create 4x4 transformation matrix including a translation

Source code in mmg_toolbox/utils/rotations.py 
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def translation_t_matrix(value=0.0, vector=(0, 0, 1), offset=(0, 0, 0)):
    """
    Create 4x4 transformation matrix including a translation
    """
    t = np.eye(4)
    translation = value * np.reshape(vector, 3) + np.reshape(offset, 3)
    t[:3, 3] = translation
    return t