Description

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 coordinates.

Examples

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)
	

See Also

ST_Dump, ST_Locate_Between_Measures