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This repository contains several Python scripts for updating and maintaining CMAP's Master Highway Network geodatabase, as well as exporting the network information into a format suitable for importing into Emme networks for travel demand modeling, which are designed to be called through tools in a custom ArcGIS Toolbox (also included in the repo).

The tools each have their own wiki page containing a detailed overview. They are listed here with a brief explanation of when they should be used:

• Generate Highway Files: to create scenario network highway files for modeling in Emme.
• Generate Transit Files: to create time-of-day-specific scenario network bus transit files for modeling in Emme.
• Import Future Bus Routes: to import new or updated planned bus route coding into the network from an Excel spreadsheet.
• Import GTFS Bus Routes: to import updated existing bus route coding (derived from current CTA & Pace GTFS data in a separate procedure) into the network.
• Import Highway Projects: to import new or updated highway project coding into the network from an Excel spreadsheet.
• Incorporate Edits: to update network topology after geometric (i.e. non-attribute) edits.
• Update Highway Project Years: to finalize project completion years for a Conformity analysis.

Additionally, the toolbox contains some secondary tools in a toolset called "Utilities", whose functions are not directly related to the day-to-day maintenance of the network, nor the generation of Emme network files, but rather for some miscellaneous tasks that use MHN data as an input:

• Export Future Network: to build the network to a future year's coded state (mainly for GTFS processing).
• Generate Directional Links: to create a copy of the MHN's roads where two-way roads are represented by two distinct line features, digitized in opposite directions
• Generate IRIS Correspondence Table: to attempt to match all MHN arterial links to an IRIS link, based on a combination of geometry and road name attributes.
• Straighten Selected Links: to remove all non-endpoint vertices from selected links, to facilitate reshaping

Finally, most of these scripts import the MHN module, which contains a wide variety of frequently used methods and constants.