| 摘要 |
PURPOSE:To facilitate judgement of room for time to a departure by calculating a departure time by a time computing means to be displayed on a display means automatically. CONSTITUTION:When a starting point, a coordinate position of a destination and a desired arrival time are inputted with an input switch 2, these data are supplied to a shortest path/time detector 11 and a DC-ROM device 9 reads road map information between the two points to be shown on a display device 10. Then, the detector 11 retrieves a shortest path and supplies shortest path information to the device 10 to be displayed on a map shown by a broken line. Along with the retrieval of the path, the detector 11 calculates a departure time and a required time and the information is supplied to the device 10 together with desired arrival time information to be displayed on a screen by characters and numerals. After the start of a running, the detector 11 replaces the current position detected with an automatic coordinate detector 1 with a starting point and calculates a required time to the destination to be displayed on the device 10. |
