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| |
| # ST_GeometricMedian |
| |
| Introduction: Computes the approximate geometric median of a MultiPoint geometry using the Weiszfeld algorithm. The geometric median provides a centrality measure that is less sensitive to outlier points than the centroid. |
| |
|  |
| |
| The algorithm will iterate until the distance change between successive iterations is less than the supplied `tolerance` parameter. If this condition has not been met after `maxIter` iterations, the function will produce an error and exit, unless `failIfNotConverged` is set to `false`. |
| |
| If a `tolerance` value is not provided, a default `tolerance` value is `1e-6`. |
| |
| Format: |
| |
| ``` |
| ST_GeometricMedian(geom: Geometry, tolerance: Double, maxIter: Integer, failIfNotConverged: Boolean) |
| ``` |
| |
| ``` |
| ST_GeometricMedian(geom: Geometry, tolerance: Double, maxIter: Integer) |
| ``` |
| |
| ``` |
| ST_GeometricMedian(geom: Geometry, tolerance: Double) |
| ``` |
| |
| ``` |
| ST_GeometricMedian(geom: Geometry) |
| ``` |
| |
| Default parameters: `tolerance: 1e-6, maxIter: 1000, failIfNotConverged: false` |
| |
| Return type: `Geometry` |
| |
| Since: `v1.4.1` |
| |
| SQL Example |
| |
| ```sql |
| SELECT ST_GeometricMedian(ST_GeomFromWKT('MULTIPOINT((0 0), (1 1), (2 2), (200 200))')) |
| ``` |
| |
| Output: |
| |
| ``` |
| POINT (1.9761550281255005 1.9761550281255005) |
| ``` |
