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Note: This function is available if you have activated the add-ons VDV 452 Import and VDV 452 Export ( Enabling or disabling add-ons). |
Via the VDV 452 interface, you can import data of the PuT data model 5.0 (described in VDV Guideline 452, 03/2008), available in Visum in VDV-452 format, version 1.4. You may also export Visum data to VDV 452.
VDV 452 is a file format for data exchange between PuT applications. The interface description in VDV Guidelines 451 and 452, as well as further information on the Association of German Transport Operators can be found at:
https://www.vdv.de/oepnv-datenmodell.aspx.
With the import, you will receive a Visum network, including a timetable. The import process is similar to the (non-additive) reading of a network. Only parts that are relevant for use in the Visum data model, including any additional attributes, are adopted from VDV 452. Line block data is also imported. During data export, the Visum data model tables that can be supplied to the VDV data model are exported as well as line block data.
Using the interface, you can import both the German and English data format. Both naming schemes defined in VDV 451 are supported, i.e. file names with a table number and files names with a table name. The language setting for data export from Visum into the VDV 452 format is German if the Visum user interface is set to German. If the user interface is set to a different language, the language setting for data export is English (Setting the language).
Due to differences between data models, the import of a VDV 452 data record might not always be congruent, and not all details maintained in Visum can be exported to VDV 452. This is why even periodic VDV 452 import and export might not always s lead to identical data records. Examples of such cases are:
- IDs of valid days: The numbers of valid days sometimes have to be adjusted, as valid day 1 is a default setting in Visum and is thus already assigned a meaning. The new numbers are also used for data export (Visum table $CALENDARPERIOD).
- Names and IDs of lines, line routes, etc.: In the PuT data model, line hierarchy objects are identified via numeric IDs, while in the Visum data model, keys are made up of the names of the respective objects (line, line route, direction, time profile). The numeric IDs are saved to user-defined attributes. When you re-import previously exported data, objects thus might have different IDs or names.
- Number of lines, etc.: During data export from Visum, only line hierarchy and network objects referenced by (active) vehicle journey sections are exported. Lines without vehicle journey sections are not included in data export, so that when you re-import data, there are less lines.
- Number of vehicle journeys: In Visum line routes may service a stop point multiple times (circle lines). This case is not provided for in the PuT data model. During data export into the VDV 452 format, these line routes are thus split into route legs. This leads to a higher number of line routes vehicle journeys also after the re-import into Visum, i.e. circle lines are then not automatically created again.
