| 摘要 |
PROBLEM TO BE SOLVED: To provide, in a short processing time, an optimum route connecting between a departure point and a destination, by judging which of a plurality of nodes is taken as a relay point of a specific route while repeatedly updating an searching region including the departure point and destination. SOLUTION: A region while containing such region as opposite to a destination E regarding a departure point S and such region as opposite to the departure point S regarding the destination E are contained, but not excessively containing these area, in short, an ellipse with the departure point S and the destination E as focal points, is searched as an searching region. If such route R1 as the departure point S and the destination E are linearly connected is present in a small searching region A1, it is obtained in early stage. Only if the route R1 is not present in the searching region A1, for example, if less nodes are contained between the departure point S and the destination E such as in mountainous area or bay, a range to be searched is expanded to a searching region A2, for obtaining a route R2. |
