Name
ST_HausdorffDistance — Returns an approximation to the Hausdorff distance between two geometries. It offers a measure of dissimilarity between the geometries.
Synopsis
double ST_HausdorffDistance(bytea GeomA, bytea GeomB);
double ST_HausdorffDistance(bytea GeomA, bytea GeomB, double
densityFrac);
Description
This algorithm computes the Hausdorff distance restricted to discrete points for one of the geometries. It is an approximation to the Hausdorff Distance based on a discretization of the input Geometry.
The points can be either the vertices of the geometries, or the geometries with line segments densified by a given fraction (if the parameter densityFrac is specified).
![[Note]](images/note.png) | |
Fraction must be in range (0.0 - 1.0) |
Coordinate Dimensions
| 2D | 3D | M |
|---|---|---|
 | | |
Spatial Standards Support
| OGC SFS for SQL. 1.1 (1999) | OGC SFS for SQL. 1.1.0 (2005) | OGC SFS for SQL. 1.2.0 (2006) | SQL-MM Part 3 |
|---|---|---|---|
| - | - | - | - |
Examples
SELECT ST_HausdorffDistance(
ST_GeomFromText('POLYGON ((1.4 1, 2 4, 4 4, 3 1, 1.4 1))'),
GeomFromText('POLYGON ((1 1, 2 4, 4 4, 3 2, 1 1))'));
--Result
0.8944271909999159
SELECT ST_HausdorffDistance(
ST_GeomFromText('POLYGON ((1.5 1.3, 2 3, 4 3, 3 1.3, 1.5 1.3))'),
GeomFromText('POLYGON ((1 1.5, 2 5, 4 3, 3 1.6, 1 1.5))'),0.5);
--Result
2.0 |  |