pgRoutingを使った経路探索方法の紹介

1. pgRouting
YAMAGUCHI Toshimitsu

2. Shortest Path Problem

4. Dijkstra's Algorithm

5. Edsger Wybe Dijkstra
(1930 5 11 - 2002 8 6

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16. Route finding with pgRouting

17. pgRouting (http://pgrouting.postlbs.org/)

18. pgRouting

19. 1
2
3

20. 1
#!/bin/sh
ogr2ogr -update -append ./allRoads/roads.shp ./aaa/a.shp -nln roads
ogr2ogr -update -append ./allRoads/roads.shp ./aaa/b.shp -nln roads
ogr2ogr -update -append ./allRoads/roads.shp ./aaa/c.shp -nln roads
ogr2ogr -update -append ./allRoads/roads.shp ./bbb/a.shp -nln roads
ogr2ogr -update -append ./allRoads/roads.shp ./bbb/b.shp -nln roads
....

21. 2
DB — PostGIS
% createdb -U postgres routing
% psql -U postgres -f [path]/lwpostgis.sql routing
% psql -U postgres -f [path]/spatial_ref_sys.sql routing

22. 2
DB — pgRouting( )
% psql -U postgres -f [path]/routing_core.sql routing
% psql -U postgres -f [path]/routing_core_wrappers.sql routing
% psql -U postgres -f [path]/routing_topology.sql routing

23. 2
DB — pgRouting(TSP)
% psql -U postgres -f [path]/routing_tsp.sql routing
% psql -U postgres -f [path]/routing_tsp_wrappers.sql routing

24. 2
DB — pgRouting(DD)
% psql -U postgres -f [path]/routing_dd.sql routing
% psql -U postgres -f [path]/routing_dd_wrappers.sql routing

25. 2
DB
% shp2pgsql ./roads.shp roads | nkf -w | psql -U postgres -d routing

26. 2
source target
ALTER TABLE routing ADD COLUMN source integer;
ALTER TABLE routing ADD COLUMN target integer;

27. 2
SELECT assign_vertex_id('routing', 0.00001, 'the_geom', 'gid');

28. <0.00001

29. 3
routing=# SELECT gid,source,target FROM roads ORDER BY
Distance(the_geom,GeomFromText('POINT(139.708 35.7076)')) limit 1;
gid | source | target
--------+--------+--------
583718 | 446827 | 446860
(1 row)
routing=#

30. 3
routing=# SELECT AsText(the_geom) FROM dijkstra_sp('roads', 273679, 273974);
astext
------------------------------------------------------------------------
MULTILINESTRING((139.862297777778 35.6611955555556,.....
...
MULTILINESTRING((139.865603888889 35.663965,139.865358055556 35.6641527777778))
(13 rows)
routing=#

33. May

34. June

35. September