def initialize_rotation_in_y(self): self.transformation_context = "rotation in y" angle = math.pi / 6.0 cosine_of_angle = math.cos(angle) sine_of_angle = math.sin(angle) self.start_position_coordinates = (1.0, 100.0, 200.0, 300.0) self.stop_position_coordinates = ( 1.0, 100.0 * cosine_of_angle + 300.0 * sine_of_angle, 200, 300.0 * cosine_of_angle - 100.0 * sine_of_angle, ) x = math.sqrt(0.4) y = math.sqrt(0.5) z = math.sqrt(0.1) self.start_direction_coordinates = (0.0, x, y, z) self.stop_direction_coordinates = ( 0.0, x * cosine_of_angle + z * sine_of_angle, y, z * cosine_of_angle - x * sine_of_angle, ) self.transformation_under_test = Transformation.rotation_about_y_axis(angle)