| 摘要 |
PROBLEM TO BE SOLVED: To provide a navigation apparatus which shortens the time required for updating map data and which reduces costs for its updating by updating the map data for each region in a prescribed range. SOLUTION: The navigation apparatus comprises a retrieval part used to retrieve a retrieval object on the basis of the map data, and a data storage part used to store the map data, and the map data are updated. The data storage stores unupdated map data together with updated map data, and the retrieval part retrieves the retrieval object included in the updated map data and the retrieval object included in the unupdated map data. COPYRIGHT: (C)2004,JPO |
