Abstract: Cartographic data is represented using polynomial splines. To improve representation accuracy and reduce storage requirements, a database storing data points (shape points and nodes) is converted into a database of spline control points. The spline control points are computed by fitting a polynomial spline to the geographic features using a least squares approximation. The control points associated with each geographic feature are stored in a computer-usable database. The geographic features can be displayed by computing the spline functions using the stored control points.

Abstract: An architecture for a geographic database that supports the identification and use of names for intersections of roads located in a geographic region, and methods for use and formation thereof. The geographic database includes data that represent components of a road network in a geographic region. The geographic database includes a first plurality of data entities each of which represents an intersection of roads in the road network and a second plurality of data entities each of which represents a name of one of the components of the road network. The geographic database includes a third plurality of data entities each of which associates one of the first plurality of data entities with one of the second plurality of data entities.

Abstract: A system and method for storing and using data representing crossings of geographic features, and an associated product having the data embodied thereon, for use with a computer based navigation system, is disclosed. A computer-readable medium has computer-readable data embodied thereon that represents geographic features in a geographic region. The computer-readable data includes a plurality of data entities of a first type each of which represents a respective one of a plurality of linearly extending geographic features and a plurality of data entities of a second type each of which represents a respective crossing at which one of the linearly extending geographic features represented by one of the plurality of data entities of the first type crosses over another of the linearly extending geographic features represented by another of the plurality of data entities of the first type at a higher altitude.