The stop ids actually _do_ have some sort of order to them. It looks like some time ago they took all of the stops, put them in alphabetical order and then numbered them accordingly. Stops on A Ave, Abernethy, Alberta tend to have very low stop ID numbers (< 75) while stops on Woodstock, Yamhill, Yeon tend to have high numbers (~6400). MLK stops are located in the "U" section (5885 = Umatilla then 5886 = MLK & Ainsworth) because it used to be named "Union Ave." Numbered stops are after the alphabetical stops. New stops are generally at the end, but sometimes inserted in random places in the middle.
Go see for yourself
3 comments:
Would have made a LOT more sense for the stop IDs to start with the route number, and then a "stop number" that would be odd for one direction (outbound?) and even for the other (inbound?)
For example - the first stop on line 58 outbound would be stop 5801, and the last possible stop would be 58999. The first inbound stop would be 5802.
Stops that have multiple routes could have multiple stop IDs that link together. This would be really valuable in the situation of Washington Square, where each "stop" has its own Stop ID instead of the Transit Center as a whole (which is useful if I want to know whether the 45 or 62 would show up first if I'm heading out Scholls Ferry Road.) So depending on the application I could specify a route-specific stop ID, but it would link to any stop at the same physical location.
Off the top of my head, several issues with that -
1) What happens if you insert a stop (do you then have to change all of the following stop ids??)
2) What happens for routes that have multiple variations (some routes have 20+ variations)
3) What happens for variations that don't start at the same point?
4) What happens when they change the route? Then stop ids would change location
IMO: The most important part is to have an ID for each location, and to have it labeled at the stop. Beyond that it's gravy to me. ;-)
1) What happens if you insert a stop (do you then have to change all of the following stop ids??)
I think at that point then we would see stop IDs out of sequence (just use the next available number, maintaining the odd/even sequence). Then again, TriMet has not been adding bus stops for the most part - if anything they've been working very hard to REMOVE bus stops under the guise of "streamlining".
2) What happens for routes that have multiple variations (some routes have 20+ variations)
I really don't think that's the case...there's a few routes that do have the multiple routes and they would have a slightly different system (i.e. 1-Vermont, 19-Woodstock, 89-Tanasbourne) and they would have a slightly modified version, but in general the stop ID system would work for them as well.
3) What happens for variations that don't start at the same point?
The Stop IDs would be for the route; so, for example, a 12-Barbur bus that starts at King City would not have its own 1201 stop - the 1201 stop would be in Sherwood. Same thing going the other way - the 1202 stop would be in Gresham; it wouldn't start over at Parkrose because some 12 trips shortline.
4) What happens when they change the route? Then stop ids would change location
Just like they do right now. TriMet started the Stop IDs before the Portland Mall construction, and had to re-do all of the downtown Stop IDs when the bus routes were moved onto 3rd/4th Avenues. And when they moved back, they were re-done all over again. No big deal.
Think of them like highway mileposts. And then wonder, if you're driving out on I-84, why there's no milepost 8 or 9. There's a milepost 7, and a milepost 10. Because when the road was realigned at some point, ODOT didn't just go and replace every milepost from there out to Ontario. Likewise, when you're on U.S. 101 near Wheeler, you'll start to see mileposts that have a "Z" suffix on them. That's again because of a road realignment. So there are, in effect, two milepost 47s, two milepost 48s, and two milepost 49s. (However, one of them is a normal milepost, and the other is a "Z" milepost.)
Of course you can't duplicate stop IDs (well, you could, but it'd add more confusion), so if you add in a stop (which, again, would be extremely rare as TriMet rarely ever adds in bus stops) you would just assign the next available number...so if the next number was, to use the Barbur example, 12503, then that new stop would use the stop ID of 12503.
If the route changes...then you've move the stop IDs over - just like ODOT would move the mileposts to the new road - ODOT wouldn't assign new mileposts to the new road while keeping the old mileposts on the old road (especially since in many cases, the old road would be removed from the ODOT road inventory.)
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