The Gauss map is a function from an Orientable Surface in Euclidean Space to a Sphere. It associates to
every point on the surface its oriented Normal Vector. For surfaces in 3-space, the Gauss map of the surface has
Degree given by half the Euler Characteristic of the surface

which works only for Orientable Surfaces.

**References**

Gray, A. ``The Local Gauss Map'' and ``The Gauss Map via Mathematica.'' §10.3 and §15.3
in *Modern Differential Geometry of Curves and Surfaces.*
Boca Raton, FL: CRC Press, pp. 193-194 and 310-316, 1993.

© 1996-9

1999-05-25