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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). Details on getting started with using these tools can be found in the getting set up wiki entry.

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).
• Export Highway Project Coding: to export data from the highway project coding table into a CSV to facilitate modification of existing coding.
• 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.
• Update MHN Base Year: to create a copy of the MHN geodatabase with the network built to a future year (a la Export Future Network) but with all highway project coding, bus routes, etc. fully intact.

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