3D nodes

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In some datasets several nodes has the same set of coordinates. That is not allowed in RW NetServer datastructure and is here refered to as 3D nodes. This is most commonly encountered in datasets, which are plane, even in the case of overpasses. Not all datasets with this problem has the needed information to even detect 3D nodes. If you are unsure if your data has this problem, send a sample to RouteWare for inspection.

If you for each link in your dataset have 2 fields with fromnode and tonode information, you can point to these fields in the makenetwork application and detect such situations, while you create the network file.

The output will be a GIS point theme ("Node_3D"), which shows the position of these situations. Same GIS format as the input is used.

The resulting file can be used in one of 3 ways:

1)

To slightly modify the coordinates in the GIS street database, so the coordinates are not the same anymore. If you choose this option, you will then have to create the network again. This is not the best approach, if you on a regular basis receive updated street networks from an external source and you have many of these situations.

2)	Combine/join the links pairwise. This requires that any other attribute information (such as streetname) is the same on both sides of the node. The same applies here as mentioned above.

3)	You can create a text file version of the coordinates of the nodes and use it as input to the turn parameter. This requires that only 2 nodes at a time have the same set of coordinates.