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ST_Scale

Signatures

GEOMETRY ST_Scale(GEOMETRY geom, DOUBLE xFactor, DOUBLE yFactor);
GEOMETRY ST_Scale(GEOMETRY geom, DOUBLE xFactor, DOUBLE yFactor, DOUBLE zFactor);

Description

Scales geom Geometry by multiplying the ordinates by the indicated scale factors. If zFactor is omitted and geom contains a z-coordinate, it is left untouched.

Examples

SELECT ST_Scale('LINESTRING(1 2, 4 5)'::Geometry, 0.5, 0.75);
-- Answer:    LINESTRING(0.5 1.5, 2 3.75)

SELECT ST_Scale('LINESTRING(1 2, 4 5)'::Geometry, 0.5, 0.75, 1.2);
-- Answer:    LINESTRING(0.5 1.5, 2 3.75)

SELECT ST_Scale('LINESTRING(1 2, 4 5)'::Geometry, 0.0, -1.0, 2.0);
-- Answer:    LINESTRING(0 -2, 0 -5)

SELECT ST_Scale('LINESTRING(1 2 3, 4 5 6)'::Geometry, 0.5, 0.75);
-- Answer:    LINESTRING(0.5 1.5 3, 2 3.75 6)

SELECT ST_Scale('LINESTRING(1 2 3, 4 5 6)'::Geometry, 0.5, 0.75, 1.2);
-- Answer:    LINESTRING(0.5 1.5 3.6, 2 3.75 7.2)

SELECT ST_Scale('LINESTRING(1 2 3, 4 5 6)'::Geometry, 0.0, -1.0, 2.0);
-- Answer:    LINESTRING(0 -2 6, 0 -5 12)
See also