It is possible, when making 3D plots from data files, for the data to be interpreted in spherical or cylindrical coordinates rather than the default Cartesian system. For details, type
help set mapping. We will give an example of using the cylindrical mapping to conveniently draw a shape with cylindrical symmetry.
The previous figure is a perspective view of a surface that somewhat resembles a Christmas tree ornament. The relevant feature of this surface is that it has rotational symmetry around the z (vertical) axis, which means that it is most naturally expressed in cylindrical coordinates.
Try the following ...