Trip generation means the calculation of the production and attraction values per zone.
Production and attraction result from the total of a variable set of numerical zone attributes, for example number of inhabitants or jobs, multiplied by coefficients (Fundamentals: Trip generation).
1. On the toolbar, click the 
Open 'Procedure sequence' window button.
The Procedure sequence window opens.
2. To the procedure sequence, at the position of your choice, add the procedure Trip generation which is provided in the Demand model category (Setting up and starting the procedure sequence).
3. In the row of the added procedure, click the button in the Reference object(s) column.
The Demand strata selection window opens.
4. In the Select demand model list, click the demand model the demand strata belong to.
5. In the Demand stratum selection list, select the demand strata you would like to calculate the trip generation for.
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Tip: To select multiple demand strata, hold down the Ctrl while clicking the desired entries one by one. |
6. Confirm with OK.
The demand strata selected are listed in the Reference object(s) column.
7. Make sure the added procedure is highlighted. Then, in the Operations section, click the Edit button.
The Trip generation parameters window opens.
8. Make the desired settings for all demand strata.
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Element |
Description |
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Calculate attributes for active zones only |
Select this option to have the attribute values calculated for active zones only. |
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Set the attributes of passive zones to 0 |
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Matrix balancing for active zones only |
Select this option to consider active zones only for scaling of sums. |
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Sum up values |
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Select this option to set the attribute values of passive zones to zero.
If the option is not activated, the attribute values of the passive zones remain unchanged.9. Specify per demand stratum how you want VISUM to calculate trip generation.
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Element |
Description |
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Demand stratum |
In this column, the selected demand strata are listed. For each demand stratum, separate settings can be made. |
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Matrix balancing |
If the production and attraction sums differ, use the drop-down list to specify the sum (productions, attractions) you want to base the trip generation on. |
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Production function
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The button opens the Production rate for <demand stratum> window. You can specify a separate production rate for each demand stratum if you enter a formula. The structure of the formula corresponds to the generation of formula attributes for zones (Fundamentals: Formula attributes) and (Type-dependent attributes).
Note If you want to use absolute production and attraction rate values, select the constant value 1.0 instead of a zone attribute. |
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Attraction function
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The button opens the Attraction rate for demand stratum window. You can specify a separate attraction rate for each demand stratum if you enter a formula. The structure of the formula corresponds to the generation of formula attributes for zones (Fundamentals: Formula attributes) and (Type-dependent attributes). Note If you want to use absolute production and attraction rate values, select the constant value 1.0 instead of a zone attribute.
Note If you want to use absolute production and attraction rate values, select the constant value 1.0 instead of a zone attribute. |
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Apply to all DStrata |
Click this button to adopt the current settings for the matrix balancing and the production and attraction rates in all demand strata. |
Use the icons to move up or down in the list of demand strata.10. Confirm with OK.
11. Execute the procedure (Executing procedures in the procedure sequence).
Trip generation is calculated. For each demand stratum the calculation results are stored as zone attributes Production and Attraction (Zones: DStrata tab and Editing the demand of Standard 4-step demand strata).
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Note: You can display the results in zone lists or in the network graphics (Displaying data graphically and in lists). |
