Skip to content

Commit

Permalink
Improve GTFS chapter
Browse files Browse the repository at this point in the history
  • Loading branch information
@estebanzimanyi
estebanzimanyi committed Jul 1, 2024
1 parent b10b2b0 commit 12a575d
Showing 1 changed file with 21 additions and 34 deletions.
55 changes: 21 additions & 34 deletions docs/GTFS.xml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,10 +25,6 @@
<para><varname>calendar_dates.txt</varname> define exceptions to the default service patterns defined in <varname>calendar.txt</varname>. There are two types of exceptions: 1 means that the service has been added for the specified date, and 2 means that the service has been removed for the specified date.</para>
</listitem>

<listitem>
<para><varname>route_types.txt</varname> contains transportation types used on routes, such as bus, metro, tramway, etc.</para>
</listitem>

<listitem>
<para><varname>routes.txt</varname> contains transit routes. A route is a group of trips that are displayed to riders as a single service.</para>
</listitem>
Expand Down Expand Up @@ -85,7 +81,6 @@ CREATE TABLE calendar (
end_date date NOT NULL,
CONSTRAINT calendar_pkey PRIMARY KEY (service_id)
);
CREATE INDEX calendar_service_id ON calendar (service_id);

CREATE TABLE exception_types (
exception_type int PRIMARY KEY,
Expand All @@ -97,19 +92,14 @@ CREATE TABLE calendar_dates (
date date NOT NULL,
exception_type int REFERENCES exception_types(exception_type)
);
CREATE INDEX calendar_dates_dateidx ON calendar_dates (date);

CREATE TABLE route_types (
route_type int PRIMARY KEY,
description text
);
CREATE INDEX calendar_dates_date_idx ON calendar_dates (date);

CREATE TABLE routes (
route_id text,
route_short_name text DEFAULT '',
route_long_name text DEFAULT '',
route_desc text DEFAULT '',
route_type int REFERENCES route_types(route_type),
route_type int,
route_url text,
route_color text,
route_text_color text,
Expand All @@ -122,15 +112,14 @@ CREATE TABLE shapes (
shape_pt_lon double precision NOT NULL,
shape_pt_sequence int NOT NULL
);
CREATE INDEX shapes_shape_key ON shapes (shape_id);
CREATE INDEX shapes_shape_id_idx ON shapes (shape_id);

-- Create a table to store the shape geometries
CREATE TABLE shape_geoms (
shape_id text NOT NULL,
shape_geom geometry('LINESTRING', 4326),
shape_geom geometry('LINESTRING', 3857),
CONSTRAINT shape_geom_pkey PRIMARY KEY (shape_id)
);
CREATE INDEX shape_geoms_key ON shapes (shape_id);

CREATE TABLE location_types (
location_type int PRIMARY KEY,
Expand All @@ -146,9 +135,9 @@ CREATE TABLE stops (
stop_lon double precision,
zone_id text,
stop_url text,
location_type integer REFERENCES location_types(location_type),
location_type integer REFERENCES location_types(location_type),
parent_station integer,
stop_geom geometry('POINT', 4326),
stop_geom geometry('POINT', 3857),
platform_code text DEFAULT NULL,
CONSTRAINT stops_pkey PRIMARY KEY (stop_id)
);
Expand All @@ -160,7 +149,7 @@ CREATE TABLE pickup_dropoff_types (

CREATE TABLE stop_times (
trip_id text NOT NULL,
-- Check that casting to time interval works.
-- Check that casting to time interval works
arrival_time interval CHECK (arrival_time::interval = arrival_time::interval),
departure_time interval CHECK (departure_time::interval = departure_time::interval),
stop_id text,
Expand All @@ -183,7 +172,6 @@ CREATE TABLE trips (
shape_id text,
CONSTRAINT trips_pkey PRIMARY KEY (trip_id)
);
CREATE INDEX trips_trip_id ON trips (trip_id);

INSERT INTO exception_types (exception_type, description) VALUES
(1, 'service has been added'),
Expand Down Expand Up @@ -218,8 +206,6 @@ COPY trips(route_id,service_id,trip_id,trip_headsign,direction_id,block_id,shape
FROM '/home/gtfs_tutorial/trips.txt' DELIMITER ',' CSV HEADER;
COPY agency(agency_id,agency_name,agency_url,agency_timezone,agency_lang,agency_phone)
FROM '/home/gtfs_tutorial/agency.txt' DELIMITER ',' CSV HEADER;
COPY route_types(route_type,description)
FROM '/home/gtfs_tutorial/route_types.txt' DELIMITER ',' CSV HEADER;
COPY routes(route_id,route_short_name,route_long_name,route_desc,route_type,route_url,
route_color,route_text_color) FROM '/home/gtfs_tutorial/routes.txt' DELIMITER ','
CSV HEADER;
Expand All @@ -233,12 +219,12 @@ CSV HEADER;
<programlisting language="sql">
INSERT INTO shape_geoms
SELECT shape_id, ST_MakeLine(array_agg(
ST_SetSRID(ST_MakePoint(shape_pt_lon, shape_pt_lat),4326) ORDER BY shape_pt_sequence))
ST_Transform(ST_Point(shape_pt_lon, shape_pt_lat, 4326), 3857) ORDER BY shape_pt_sequence))
FROM shapes
GROUP BY shape_id;

UPDATE stops
SET stop_geom = ST_SetSRID(ST_MakePoint(stop_lon, stop_lat),4326);
SET stop_geom = ST_Transform(ST_Point(stop_lon, stop_lat, 4326), 3857);
</programlisting>
The visualization of the routes and stops in QGIS is given in <xref linkend="stib" />. In the figure, red lines correspond to the trajectories of vehicles, while orange points correspond to the location of stops.
</para>
Expand All @@ -253,20 +239,20 @@ SET stop_geom = ST_SetSRID(ST_MakePoint(stop_lon, stop_lat),4326);
<sect1>
<title>Transforming GTFS Data for MobilityDB</title>
<para>
We start by creating a table that contains couples of <varname>service_id</varname> and <varname>date</varname> defining the dates at which a service is provided.
We start by creating a table that contains couples of <varname>service_id</varname> and <varname>date</varname> defining the dates at which a service is provided.
<programlisting language="sql">
DROP TABLE IF EXISTS service_dates;
CREATE TABLE service_dates AS (
SELECT service_id, date_trunc('day', d)::date AS date
FROM calendar c, generate_series(start_date, end_date, '1 day'::interval) AS d
WHERE (
(monday = 1 AND extract(isodow FROM d) = 1) OR
(tuesday = 1 AND extract(isodow FROM d) = 2) OR
(wednesday = 1 AND extract(isodow FROM d) = 3) OR
(thursday = 1 AND extract(isodow FROM d) = 4) OR
(friday = 1 AND extract(isodow FROM d) = 5) OR
(saturday = 1 AND extract(isodow FROM d) = 6) OR
(sunday = 1 AND extract(isodow FROM d) = 7)
(monday = 1 AND extract(isodow FROM d) = 1) OR
(tuesday = 1 AND extract(isodow FROM d) = 2) OR
(wednesday = 1 AND extract(isodow FROM d) = 3) OR
(thursday = 1 AND extract(isodow FROM d) = 4) OR
(friday = 1 AND extract(isodow FROM d) = 5) OR
(saturday = 1 AND extract(isodow FROM d) = 6) OR
(sunday = 1 AND extract(isodow FROM d) = 7)
)
EXCEPT
SELECT service_id, date
Expand Down Expand Up @@ -304,8 +290,8 @@ FROM trips t JOIN stop_times s ON t.trip_id = s.trip_id;

UPDATE trip_stops t
SET perc = CASE
WHEN stop_sequence = 1 then 0.0
WHEN stop_sequence = no_stops then 1.0
WHEN stop_sequence = 1 THEN 0.0
WHEN stop_sequence = no_stops THEN 1.0
ELSE ST_LineLocatePoint(g.shape_geom, s.stop_geom)
END
FROM shape_geoms g, stops s
Expand Down Expand Up @@ -441,7 +427,8 @@ CREATE TABLE trips_mdb (
);

INSERT INTO trips_mdb(trip_id, service_id, route_id, date, trip)
SELECT trip_id, service_id, route_id, date, tgeompoint_seq(array_agg(tgeompoint_inst(point_geom, t) ORDER BY T))
SELECT trip_id, service_id, route_id, date, tgeompointSeq(array_agg(
tgeompoint(point_geom, t) ORDER BY T))
FROM trips_input
GROUP BY trip_id, service_id, route_id, date;

Expand Down

0 comments on commit 12a575d

Please sign in to comment.