[Talk-us] Network edge cases

[Minh Nguyen]

Vào lúc 08:20 2022-01-27, Paul Johnson đã viết:
> I feel like we should nail down the hierarchy a bit... it's 
> US:ST:County:City, right?  If not, that makes more sense than just 
> US:ST:Locale just to cover the edge case potential for two towns with 
> the same name in the same state (rare, but not unheard of) or a county 
> with the same name as a city within it that both have their own networks.

I agree with including the county in the network in states where that 
hierarchy makes sense. In Ohio, we've been using the same format for 
both city and township route networks. However, I'm aware that this 
hierarchy would be less intuitive in some other states, such as 
Virginia, if the situation ever arises.

Ohio has lots of independently maintained township route networks, and 
there are conflicts requiring disambiguation. For example, Holmes and 
Jefferson counties both have a Knox Township. These two townships have 
overlapping route numbering schemes and distinct shields. [1][2] So far, 
I know of several conflicts relevant to a shield renderer:

* Knox townships in Holmes and Jefferson counties
* Monroe townships in Logan and Holmes counties
* Paint townships in Holmes and Wayne counties
* Salem townships in Tuscarawas and Washington counties
* Salt Creek townships in Holmes and Wayne counties
* York townships in Medina and Morgan counties

For the Fremont city route network, I used US:OH:SAN:Fremont. [3] I put 
this city at the same level of the hierarchy as townships, collapsing a 
half-step distinction made in admin_level. Even though there are cities 
and villages that share a name with their surrounding or neighboring 
township in the same county, I think we have enough of a handle on the 
existing city route networks to know this won't be a problem in 
practice. Unfortunately, the Fremont shields are as plain as can be: 
just a white rectangle saying "City Route".

[1] 
https://commons.wikimedia.org/wiki/File:Knox_Township_Route_204,_Holmes_County,_Ohio.svg
[2] 
https://commons.wikimedia.org/wiki/File:Knox_Township_Route_242,_Jefferson_County,_Ohio.svg
[3] SAN is the standard three-letter code for Sandusky County. We've 
standardized on ODOT's three-letter county codes because they're 
frequently signposted as part of the state's reference location system.

-- 
minh at nguyen.cincinnati.oh.us