🧹 Chore: Document network requirements

[lmz]

This chore is to document the network requirements in tm2py.

I expect this will be derived from a combination of sources:

• google doc on network design
• ranch/lasso methods
• tm2py skimming/assignment code
• https://github.com/BayAreaMetro/tm2py/blob/master/tm2py/components/network/highway/highway_network.py#L111

I will do this but pinging @DavidOry who recommends doing this via pedantic data model.

[i-am-sijia]

Hi @lmz, are you looking for requirements on network attribute names, e.g., conversion from the standard attribute names to the model attribute names, or broader than that, e.g., what values are allowed, network input file format, etc.

[lmz]

Good question! All of the above -- basically, what do I have to have in this network so it'll work?

[i-am-sijia]

@lmz would something like this be a start? I can add more. This is an example for the node table.

Standard Attribute	EMME Attribute	Data Type	Note	Conversion Script	Used in tm2py modules
model_node_id	#node_id	int	numbered by county-based rules	Lasso/emme.py	yes
osm_node_id	#osm_node_id	str			no
shst_node_id	N/A	str		N/A	no
county	#node_county	str			yes
drive_access	@drive_node	int	used in Lasso to filter nodes for EMME network	Lasso/emme.py	no
walk_access	@walk_node	int	used in Lasso to filter nodes for EMME network	Lasso/emme.py	no
bike_access	@bike_node	int	used in Lasso to filter nodes for EMME network	Lasso/emme.py	no
rail_only	@rail_node	int	used in Lasso to filter nodes for EMME network	Lasso/emme.py	no
X	x	float	converted to MTC crs	Lasso/emme.py	yes
Y	y	float	converted to MTC crs	Lasso/emme.py	yes
farezone	@farezone	int		Lasso/emme.py	yes
model_node_id	@taz_id	int	only for TAZ nodes	Lasso/emme.py	yes
model_node_id	@maz_id	int	only for MAZ nodes	Lasso/emme.py	yes
model_node_id	#node_type	str		Lasso/emme.py	no