plane spiric curve


last updated: 2003-08-01

The conic section can be constructed as the intersection of a conic with a plane. Replacing the conic by a torus, we get the plane spiric curve 1).
The curve is a bicircular quartic.

When the plane is parallel to the axis of the torus (a=2, c=0), a spiric section is formed.


1) speira (Gr.) = torus