PostGIS
Description
Tests if a geometry encodes a valid trajectory. A valid trajectory is
represented as a LINESTRING with measures (M values). The measure
values must increase from each vertex to the next.
Valid trajectories are expected as input to spatio-temporal functions like ST_ClosestPointOfApproach
Availability: 2.2.0
This
function supports 3d and will not drop the z-index.
Examples
-- A valid trajectory
SELECT ST_IsValidTrajectory(ST_MakeLine(
ST_MakePointM(0,0,1),
ST_MakePointM(0,1,2))
);
t
-- An invalid trajectory
SELECT ST_IsValidTrajectory(ST_MakeLine(ST_MakePointM(0,0,1), ST_MakePointM(0,1,0)));
NOTICE: Measure of vertex 1 (0) not bigger than measure of vertex 0 (1)
st_isvalidtrajectory
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