Name
ST_Force4D — Force the geometries into XYZM mode.
Synopsis
geometry ST_Force4D(geometry geomA, float Zvalue = 0.0, float Mvalue = 0.0);
Description
Forces the geometries into XYZM mode. Zvalue and Mvalue is tacked on for missing Z and M dimensions, respectively.
Changed: 2.1.0. Up to 2.0.x this was called ST_Force_4D.
Changed: 3.1.0. Added support for supplying non-zero Z and M values.
This function supports 3d and will not drop the z-index.
This method supports Circular Strings and Curves
Examples
--Nothing happens to an already 3D geometry
SELECT ST_AsEWKT(ST_Force4D(ST_GeomFromEWKT('CIRCULARSTRING(1 1 2, 2 3 2, 4 5 2, 6 7 2, 5 6 2)')));
st_asewkt
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CIRCULARSTRING(1 1 2 0,2 3 2 0,4 5 2 0,6 7 2 0,5 6 2 0)
SELECT ST_AsEWKT(ST_Force4D('MULTILINESTRINGM((0 0 1,0 5 2,5 0 3,0 0 4),(1 1 1,3 1 1,1 3 1,1 1 1))'));
st_asewkt
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MULTILINESTRING((0 0 0 1,0 5 0 2,5 0 0 3,0 0 0 4),(1 1 0 1,3 1 0 1,1 3 0 1,1 1 0 1))