Under Impedance Matrix:
- Matrix file: Skim Tree
(The skim tree matrix created in Task 2) - Matrix: Matrix 1
(The default name of the skim tree matrix. A matrix file can contain more than one matrix.) - Click HBOFF under matrix to highlight it, and apply the same procedure using HBO_FF as F-Factors). Repeat for NHBFF as well. Click OK when finished.
transcad uses the friction factor lookup table to generate friction factors for each zone pair, fills the selected matrices, and display a status report with Notepad. Note: Changes to the Friction Factor Shell may not display until the matrix is refreshed -- minimize the window then restore it. The changed values should appear.
4.2 Applying the Gravity Model
This task utilizes the Task 4 Trip Generation results with the Task 5.1 Friction Factor Analysis to apply the Gravity Model and produce a trip table for each defined trip purpose.
Go to File / Open (type dataview) and open balanced.dvw. Make sure that ff.mtx is also openned. Go to Planning / Trip Distribution / Gravity Evaluation. The Gravity Evaluation dialog box will appear.
Under "Production-Attraction Data," enter:- Dataview: TAZ + TRIPS (this is balanced.dvw)
- Records: All Features
On the "General" tab, enter under "Purpose Information for New":
- Name: HBW
- Productions: TRIPS.FHBW_P
- Attractions: TRIPS.FHBW_A
Under "Other Information for HBW," enter:
