Returns the element of a geometry object that matches the specified M coordinate.
Syntax
geometry ST_LocateAlong(geometry ageomWithMeasure, float8 aMeasure, float8 offset)Parameters
| Parameter | Description |
|---|---|
ageomWithMeasure | The geometry object to query. |
aMeasure | The M coordinate value to match. |
offset | The offset distance applied during computation. A positive value offsets to the left; a negative value offsets to the right along the input line. |
Usage notes
This function supports only geometry objects that have M coordinates.
This function does not support polygon objects.
Examples
SELECT ST_AsText(ST_LocateAlong(ST_GeomFromText('MultiPointM((1 2 3),(5 4 3),(4 5 6))'),3));
st_astext
----------------------------
MULTIPOINT M (1 2 3,5 4 3)
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