Create a graph for Spiess & Florian's algorithm from the transit data model

The GTFS for the Lyon test case has been imported into the transit database. The goal is to create the graph for the assignment using Spiess & Florian's algorithm.

Assumptions

In the first approach, we do not deal with:

• fares
• vehicle capacity

This will be dealt with in another iteration.

Input tables

We are going to use the 5 following tables:

• stops
• routes
• route_links
• trips
• trips_schedule

stops

shape: (4496, 13)

	stop_id	stop	agency_id	link	dir	name	parent_station	description	street	fare_zone_id	transit_zone	route_type	geometry
dtype	int64	object	int64	object	object	object	object	object	object	object	object	int64	object
example	10000000002	2	1	None	None	Thurins Mairie	1			None	None	1	b"\x00\x01\xe6\x10\x00\x00'\xf6\xd0>V\x90\x12@...
nunique	4496	4496	1	0	0	2049	2054	1	1	0	0	1	2054

Remarks (for the present case):

• stop, parent_station could be of int64 type
• link, dir, description (""), street (""), fare_zone_id and transit_zone are empty
• rout_type is always 1

routes

shape: (475, 11)

	pattern_id	route_id	route	agency_id	shortname	longname	description	route_type	seated_capacity	total_capacity	geometry
dtype	int64	int64	object	int64	object	object	object	int64	int64	int64	object
example	10001001000	10001000000	11	1		11		1	280	560	b'\x00\x01\xe6\x10\x00\x00'\xf6\xd0>V\x90\x12...
nunique	475	141	141	1	1	141	1	1	1	1	465

Remarks (for the present case):

• route could be of int64 type
• shortname (""), description ("") are empty
• rout_type is always 1

route_links

shape: (9637, 7)

	transit_link	pattern_id	seq	from_stop	to_stop	distance	geometry
dtype	int64	int64	int64	int64	int64	float64	object
example	20000001	10001001000	0	10000000002	10000000006	353.155972	b"\x00\x01\xe6\x10\x00\x00'\xf6\xd0>V\x90\x12@...
nunique	9637	475	46	4435	4401	2650	4613

trips

shape: (17653, 4)

	trip_id	trip	dir	pattern_id
dtype	int64	object	int64	int64
example	10001001001	1	0	10001001000
nunique	17653	17653	1	475

Remarks (for the present case):

• trip could be of type int64

trips_schedule

shape: (388377, 4)

	trip_id	seq	arrival	departure
dtype	int64	int64	int64	int64
example	1.0001e+10	0	21600	21600
nunique	17653	47	10095	10095

Remarks:

• arrival and departure times are expressed in seconds from 00h00m00