Updating SOABM For New Versions of Visum

Updating SOABM for Visum

This page captures some helpful reminders of where changes need to be made in the SOABM setup each time a new version of Visum is desired to be used with SOABM.

Script Changes

Two scripts have Visum version pointers as initial parts of the script (in the header):

• Master_Runner.Py
• inputChecker.py

Both of these pointers need to be changed to the desired version.

Bat File Changes

The bat file is an additional important step. Two lines in the setup portion of the bat file refer to the Visum version. These two lines, copy over the dll (and related bmp image) from the run folder to the user vdf folder that Visum accesses. While this is file transfer really only needs to be done once (not completed every time the model, or bat file, is run), the reason it is built into the bat file is because:

1. if the file is missing, Visum runs without a warning to the user and it produced significantly different results.
2. the location of the file for Visum to access is user specific. So ODOT was having issues where a machine was properly setup to run the ABM for one user and then a different user would log-in and get different results because the dll was not copied to their user specific folder for Visum to access. In discussion with PTV (authors of Visum), the reason for this is that updating dll's for all users requires administrative rights, and it can create a dangerous situation if dlls are being updated in core files (core files for all users), so having user specific dll that can be custom built (like for SOABM), gives users flexibility with building custom VDFs, without the risk of inadvertently corrupting the software by updating a central dll file.

Important Reminders

The three files above (2 scripts and the bat file) should be all that is needed to update to the latest Visum. However, other complications and issue are possible each time a new Visum is linked with the ABM, and users should ensure to verify that ABM results have not significantly shifted between assignment software versions. At the time of this wiki page, ODOT was shifting from Visum 2020 to 2022. At that time SOABM was written in Python 3.7 and Visum was shifting to 3.9. The code and libraries for 3.7 still work for 2022, but the farther removed Visum gets from the original build, the more likely python connections between the ABM and Visum will need to be updated and/or the snap shot dependencies will need to be updated. If changing the three files above does not create a successful shift to the latest version of Visum, it is likely python updates will be needed as well (which can be significantly more complicated).