For the network currently loaded, you can select a different coordinate system. This is necessary, for example, if your current network uses the Visum coordinate system and you want to import input data in a specific projection (Fundamentals: Coordinate systems).
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Notes: By default Visum uses its own Visum coordinate system. A set of coordinate systems is provided as files, with the extension *.prj, in the directory ...\Exe\Projections of your Visum installation (Editing the storage location of files). The format of the files is *.wkt (well-known text format). |
Depending on the coordinate systems between which you switch this may have different effects:
- When switching from the Visum coordinate system to another coordinate system, you decide that the previously used coordinates belong to the newly selected coordinate system. Neither the coordinates nor the display will change.
- If you switch between two pre-defined coordinate systems, Visum will transform the data. Both display and coordinates will change.
- If you switch back from a pre-defined coordinate system to the Visum system, neither the coordinates nor the display will change.
1. From the Network menu, choose Network settings.
The Network settings window opens.
2. Select the Co-ordinate system tab.
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Note: Based on the set option Visum (no projection) and From file, you can see which coordinate system is currently selected. |
3. Select the desired options:
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Element |
Description |
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Visum (no projection) |
If this option has been selected, you will switch to the Visum coordinate system. Neither the coordinates nor the display will change. |
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From file |
If this option has been selected, you will switch to a pre-defined coordinate system. Via the adjacent button, select the desired coordinate system in the Projections window. Notes Make sure that the selected coordinate system matches your data. If you want to switch between two pre-defined coordinate systems, first of all you have to switch to the world-wide applicable GCS WGS 84 coordinate system and then to the desired system. This is to ensure that the date (= the zero point of the coordinate system) is converted correctly. You will find the GCS WGS 84 coordinate system in the Projections window under Geographic Coordinate Systems > World > WGS 1984.prj. |
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Transform coordinates in case of changes |
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If this option has been selected, the coordinates are transformed automatically and the network display is refreshed.
If this option has not been selected, the coordinate values remain unaltered when switching the system. This setting is helpful, for example, if the wrong coordinate system has previously been defined for the available coordinate values.|
Notes: Once you have changed the coordinate system, performed actions cannot be undone. If you change the coordinate system, the lengths of line objects (for example links, connectors and line route items) may alter, too. If required, they must be explicitly recalculated (Recalculating lengths). |
4. Confirm with OK.
The coordinate system is changed.
