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| |
| # ST_LocalOutlierFactor |
| |
| Introduction: Computes the Local Outlier Factor (LOF) for each point in the input dataset. |
| |
| Local Outlier Factor is an algorithm for determining the degree to which a single record is an inlier or outlier. It is |
| based on how close a record is to its `k` nearest neighbors vs how close those neighbors are to their `k` nearest |
| neighbors. Values substantially less than `1` imply that the record is an inlier, while values greater than `1` imply that |
| the record is an outlier. |
| |
| !!!Note |
| ST_LocalOutlierFactor has a useSphere parameter rather than a useSpheroid parameter. This function thus uses a spherical model of the earth rather than an ellipsoidal model when calculating distance. |
| |
|  |
| |
| Format: `ST_LocalOutlierFactor(geometry: Geometry, k: Int, useSphere: Boolean)` |
| |
| Return type: `Double` |
| |
| Since: `v1.7.1` |
| |
| SQL Example |
| |
| ```sql |
| SELECT ST_LocalOutlierFactor(geometry, 5, true) |
| ``` |
| |
| Output: |
| |
| ``` |
| 1.0009256283408587 |
| ``` |
