| 摘要 |
PURPOSE:To search for a correct guide route according to running direction regulation. CONSTITUTION:Crosses having running direction regulation are defined by a combination of a plurality of cross nodes constructed in a link to distinguish possible running directions on road data stored in a CD-ROM 11 while adjacent cross nodes in directions where an automobile cannot drive from the cross node of interest are not included in a cross net list. When an optimum route searching part 15f searches for an optimum route by referring to the cross net list, the optimum route is obtained with routes with change in direction close to 180 degrees at the cross having the running direction regulation eliminated. |
