ST_Locate_Along_Measure — Return a derived geometry collection value with elements that match the specified measure. Polygonal elements are not supported.
geometry ST_Locate_Along_Measure(
geometry ageom_with_measure, float a_measure)
;
Return a derived geometry collection value with elements that match the specified measure. Polygonal elements are not supported.
Semantic is specified by: ISO/IEC CD 13249-3:200x(E) - Text for Continuation CD Editing Meeting
Availability: 1.1.0
Use this function only for geometries with an M component |
This function supports M coordinate.
SELECT ST_AsEWKT(the_geom) FROM (SELECT ST_Locate_Along_Measure( ST_GeomFromEWKT('MULTILINESTRINGM((1 2 3, 3 4 2, 9 4 3), (1 2 3, 5 4 5))'),3) As the_geom) As foo; st_asewkt ----------------------------------------------------------- GEOMETRYCOLLECTIONM(MULTIPOINT(1 2 3,9 4 3),POINT(1 2 3)) --Geometry collections are difficult animals so dump them --to make them more digestable SELECT ST_AsEWKT((ST_Dump(the_geom)).geom) FROM (SELECT ST_Locate_Along_Measure( ST_GeomFromEWKT('MULTILINESTRINGM((1 2 3, 3 4 2, 9 4 3), (1 2 3, 5 4 5))'),3) As the_geom) As foo; st_asewkt --------------- POINTM(1 2 3) POINTM(9 4 3) POINTM(1 2 3)