H2GIS

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ST_3DLength

Signature

DOUBLE ST_3DLength(GEOMETRY Linestring);

Description

Returns the 3D length of a (multi)Linestring.

In the case of a 2D Geometry, ST_3DLength returns the same value as ST_Length.

Note that (multi)points, (multi)polygons or GeometryCollections return 0.0.

Examples

SELECT ST_3DLength('LINESTRING(1 4, 15 7, 16 17)');
-- Answer: 24.367696684397245 = SQRT(205) + SQRT(101)

SELECT ST_3DLength('LINESTRING(1 4 3, 15 7 9, 16 17 22)');
-- Answer: 31.955851421415005 = SQRT(241) + SQRT(270)

SELECT ST_3DLength('MULTILINESTRING((1 4 3, 15 7 9, 16 17 22),
                                    (0 0 0, 1 0 0, 1 2 0, 0 2 1))');
-- Answer: 36.3700649837881 = SQRT(241) + SQRT(270) + 3 + SQRT(2)
See also