UniformSpherical( I, R)

Generates points uniformly on a sphere (or circle or hypersphere). Each sample generated is indexed by I -- so if I has 3 elements, the points will lie on a sphere.

The mid value is a bit strange here since there isn't really a median that lies on the sphere. Obviously the center of the sphere is the middle value, but that isn't in the allowable range. So, an arbitrary point on the sphere is used.