| 摘要 |
PROBLEM TO BE SOLVED: To accurately retrieve a place name by an index assigned to road data. SOLUTION: The CPU having completed the determination of a present position examines first whether the present position is on the road (step 110). If it is not on the road, road data for proximate retrieval position is retrieved from a road data table (step 120); if on the road, the relative road data, i.e., road data for retrieval position is retrieved. Then, the CPU jumps to the address of the index for retrieving a place name assigned to the road data so retrieved (step 130), reading out the place name data corresponding to such address (step 140), and specifies the place name (step 150). If the present position changes, the process is repeated from the beginning. |
