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superqwert

The numbers on 389 and 631 agree with my post linked above to 3SF... Rerunning my previous query on 53 gets me:

min: 11.176937891670061

lq: 69.77607205565486

med: 147.79705350080133

avg: 219.3995096050874

uq: 291.84606245281907

max: 1121.239174918762

I wonder where you got your csv data from exactly? I found a csv (https://tfl.gov.uk/cdn/static/cms/documents/stop-sequences-e...) that is labelled "The example feeds below are not updated and for demonstration purposes only".

For my query I called the route sequence API directly:

https://api.tfl.gov.uk/line/53/Route/Sequence/inbound

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The CSV is this one - http://tfl.gov.uk/tfl/syndication/feeds/bus-sequences.csv?ap...

I get the same sequence of stops from that API link that the CSV has for route 53, run 2, albeit with northing/easting location instead of lat/long.

(I'm extremely sceptical about the 11m minimum distance too - having done the entire 53 route a few times, I can't remember any stops that are basically on top of each other.)

I think I've found the issue with the 11m distance - the 11m distance is:

[-0.126102, 51.502769] to [-0.126018, 51.502714]

What is happening is that the TfL sequence API is starting the bus route sequence on one side of the road of Parliament Street, before turning it around at the corner with Whitehall Place. The bus stops on either side of the road are very close together. Other maps/sequences elsewhere start the sequence at the end of Parliament Street, meaning the short distance is avoided.

Ah, you're parsing the `lineStrings` blob? I'm looking at the lat/long pairs in the `stopPointSequences` structure[1] which gives a different set of coords (in particular, 51.502769, -0.126102 doesn't exist as a stop for the 53.)

Interesting! I wonder why the Line strings blob differs... Maybe it doesn't represent bus stops at all, but points at which the route changes for the purpose of drawing?

It does seem to be "the route as you'd show on a map" - if I plot the two sets points on GPSVisualizer, it's fairly different.

https://imgur.com/a/BUSW3C2

I guess the 389/631 routes are reasonably simple and don't need more "drawing points" than you'd get from the bus stops anyway?

[edit: added the 389 bus stops and line points to the imgur gallery]

nice!

but then... why would my query have matched your query in the cases of 389 and 631?!

In fact, it seems for 53 that none of the lineStrings match the stopPointSequence lat/lons

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