ST_IsValidTrajectory
Prev  7.20. Trajectory Functions  Next

Name

ST_IsValidTrajectory — Tests if the geometry is a valid trajectory.

Synopsis

boolean ST_IsValidTrajectory(geometry line);

Descrizione

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

Disponibilità: 2.2.0

Questa funzione supporta il 3d e non distrugge gli z-index.

Esempi

-- 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
----------------------
 f