Vehicle-route computing apparatus

摘要

Routes from a departure area to a plurality of destination areas are found as a departure-area route network data set and a plurality of such departure-area route network data sets computed for all departure areas are then stored in advance in a road-map storing memory unit 4 and a departure-area route network data storing memory unit 5. At a route-search time, a departure-area determining unit 3 determines the departure area of the vehicle to which a departure position pertains and a route-search processing means 7 uses a departure-area route network data set for the departure area determined by the departure-area determining unit 3 as well as road maps of the departure area and the vicinity of a departure position to search for guidance routes from the departure position to the destination position in a short time, presenting the guidance routes to the driver.