Parameters of direct assignment
Direct assignment: Basis tab
Element |
Description |
Recalculate demand matrix |
If this option has been checked, the demand matrix of the selected demand segment is recalculated. If the demand segment is not connected to a demand matrix (Connecting demand matrices and demand segments), a new demand matrix is automatically created. Note The demand matrix data result from the path volumes read from file with the survey data records (Num Pass). In the survey data file, a projection factor (ExtProjFactor) can be entered by data record. The values are multiplied when being read from file. In this way, passenger weighting performed outside of Visum can be regarded for the direct assignment. |
Calculate skim matrices |
Select this option to calculate the skim matrices selected in the Skim matrices tab (Settings for PuT skim matrix calculation). Note You cannot calculate the following skims because the direct assignment does not store the required parameters for calculation.
|
Zone selection |
Origin zones Via these entries you may restrict the calculation to the demand of the selected origin zones. Thus only the selected rows of the demand matrix will be assigned. Note If both entry fields are empty, Visum will assign the entire demand matrix. If only a single zone number is entered, Visum will use this value as the upper or lower limit respectively (half-open interval). Analyzed OD pairs Use this list box to restrict the amount of analyzed OD pairs to active OD pairs, active origin zones, or pairs of active zones only. Note The options Origin zones and Analyzed OD pairs can be combined. |
Assignment time period |
Use the entry fields to specify the assignment time period. Notes The direct assignment regards only paths with a departure time within the assignment time period. The departure time of a path indicates that moment in time when the passenger starts walking from his origin to the public transport stop. If a calendar is used, you need to select a weekday or a date (Selecting a calendar ). |
Direct assignment: Skim matrices tab
You only have to set parameters for skim matrix calculation if you want to calculate an assignment and skim matrices simultaneously (Settings for PuT skim matrix calculation).
Note: To have skim matrices calculated, in the Basis tab, select Calculate skim matrices. |