Get & set allow the user to get or set values for specific methods. Some methods allow the user to set and get using the same method.

	DSegment3d    double Length { get;
}
	double distance = segmentD3d.Length;
	DRay3d   DPoint3d Origin { get; set; }
	DPoint3d ptD3d = rayD3d.Origin
	rayD3d.Origin = ptD3d