> This makes it possible to build a worldwide geographic database with no seams or singularities The geographic database may have no singularities but the coor

> This makes it possible to build a worldwide geographic database with no seams or singularities The geographic database may have no singularities but the coordinate system used does. The coordinate system has a singularity at the origin since it is just an equivalence class on R^3 / {0} but probably (I don't know the domain well) this never comes up in practice.