Exporting shape and GeoJSON files

Note: Exporting shape and GeoJSON files is only possible with the add-on module GIS interface shape.

Exporting shape and GeoJSON files can be useful if, for example, you want to use calculation results such as link volumes from a Visum assignment in a GIS. These files can also be used to exchange data with other users who only work with GIS and do not have a Visum installation.

For network objects nodes, stop points, stops, links, zones, main zones, territories, line routes, screenlines, connectors, POIs and detectors, binary shape files can be saved directly from Visum respectively. For each network object type you select, a file with the extension *.shp, *.shx, and *.dbf is saved. Additionally, Visum creates a *.ctf file for each exported shape file. Visum renames attribute identifiers, which are longer than 10 characters, because shape files do not support attribute identifiers with more characters. This is documented in the *.ctf file.

If a projection is defined in Visum, Visum creates a *.prj file for each network object type, with the currently set projection (apart from during the setting Visum, which means no projection). This does not guarantee that when reading the shape file to another network, which has a different projection of coordinates, the coordinates of this network remain constant.

GeoJSON files can generally contain elements of several geometry types (Point, LineString, MultiPolygon). However, when exporting GeoJSON files from Visum, only files that contain elements of one type are saved. The GeoJSON export saves files that also comply with the RFC 7946 specification, i.e. in particular use WGS-84 as the reference coordinate system.

The Table 282 shows the shape or GeoJSON geometry types to which the Visum network objects are mapped.

Table 282: Mapping of Visum data to shape or GeoJSON geometry types

 

Point

Polyline

Polygon

Node

X

 

 

Main nodes

 

 

X

Main node centroids

X

 

 

Stop points

X

 

 

Stops

X

 

 

Links

 

X

 

Zones

 

 

X

Zone centroids

X

 

 

Main zones

 

 

X

Main zone centroids

X

 

 

Territories

 

 

X

Territory centroids

X

 

 

Line routes

 

X

 

Screenlines

 

X

 

Connectors

 

X

 

Count locations

X

 

 

Detectors

X

 

 
POI centroids

X

    
POI polylines  

X

  
POI polygons    

X

When exporting shape or GeoJSON files, the following special cases must be taken into account.

  • Links

If links are saved undirected, only one object is created for both directions. The attributes of the From node keep their name. Attributes of the opposite direction all start with an "R_". If the option Directed is selected (only available when exporting shape files), an individual object is saved in the shape file for each direction.

  • Connectors

For shape file exports, you can select whether the first point of the object should be the zone (standard setting) or the node. For each single object the attributes of both directions are always stored. Reverse attributes contain the entry „R_“ as prefix. The specified direction is always taken.

  • POIs

POIs can be point, polygon or polyline and are thus exported to three different files.