H2GIS

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ST_Normalize

Signature

GEOMETRY ST_Normalize(GEOMETRY geom);

Description

Converts a Geometry to its normal (or canonical) form. The definitions for normal form use the standard lexicographical ordering on coordinates.

Examples

SELECT ST_Normalize('POLYGON((2 4, 1 3, 2 1, 6 1, 6 3, 4 4, 2 4))');
-- Answer:           POLYGON((1 3, 2 4, 4 4, 6 3, 6 1, 2 1, 1 3))

SELECT ST_Normalize('MULTIPOINT((2 2), (2 5), (10 3), (7 1),
                                (5 1), (5 3))');
-- Answer:           MULTIPOINT((2 2), (2 5), (5 1), (5 3),
--                              (7 1), (10 3))

SELECT ST_Normalize('LINESTRING(3 1, 6 1, 6 3, 3 3, 1 1)');
-- Answer:           LINESTRING(1 1, 3 3, 6 3, 6 1, 3 1)
See also