The definition of Toroidal surface is mentioned here:
Toroidal surfaces are formed by defining a curve in the Y-Z plane, and then rotating this curve about an axis parallel to the Y axis and intersecting the Z axis. Toroids are defined using a base radius of curvature in the Y-Z plane, as well as a conic constant and polynomial aspheric coefficients.
Another way to verify, we can use the surface sag, the rotation R’s value is 0：
This is a trick to test some unfamiliar surface, we can use Surface sag and surface sag cross to test.