The slope is a link attribute. It is used amongst other things for the following purposes:
- ANM export to Vissim
- ICA calculations
- Emission calculation according to HBEFA
Visum can only calculate the slope of a link if the z-coordinates of the From-node and To-node of the link are known (Editing the attribute values of nodes). The slope is displayed in percentages.
Visum calculates the slope for one link direction. The opposite direction gets the same slope value with reversed sign, however.
You can execute the functionality for all, all active links, or links marked in the network editor.
Editing all or all active links
1. If required, set the links active, whose slope you want to calculate, via
- the spatial selection (Setting network objects active/passive via the spatial selection) and/or
- filter criteria (Using filters to set network objects active or passive).
The selected links are active.
2. In the Network window, right-click the Links button.
The Links shortcut menu opens.
3. Select the Calculate slope from z-coordinates entry.
The Calculate slope from z-coordinates window opens.
4. Make the desired changes.
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Element |
Description |
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Only edit active objects |
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Reference attribute for length |
Length (input attribute) You can read the link attribute or have it calculated by Visum and edit it afterwards Select this reference attribute if you have reliable length data. This way you will get the most accurate results. Length direct This link attribute stands for the direct distance between the From-node and the To-node. It is calculated automatically by Visum. Length polygon This link attribute specifies the length of the polygon between the From-node and the To-node. It is calculated automatically by Visum. |
If this option has been selected, only the slopes of active links will be calculated.
If this option has not been selected, the slopes of all links will be calculated.5. Confirm with OK.
Visum calculates the slopes of the links you specified. The slope is displayed as a link attribute in percent. You will also find the slope details on the Environment tab of the Edit link window (Properties and options of links).
Editing marked links
1. In the network, mark all links whose slope you want to calculate.
2. Right-click in the network display.
A shortcut menu opens.
3. Select the Calculate slope from z-coordinates entry.
4. Make the desired changes.
5. Confirm with OK.
Visum calculates the slopes of the selected links.
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Tip: You can also call the function from the shortcut menu of the corresponding list and edit marked objects together. |
