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## Voronoi
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Function to construct the [Voronoi Diagram ](https://en.wikipedia.org/wiki/Voronoi_diagram ) from a dataset of scatter points, clipped to the significant area
PostGIS wil include this in future versions ([doc for dev branch](http://postgis.net/docs/manual-dev/ST_Voronoi.html)) and will perform faster for sure, but in the meantime...
### CDB_Voronoi (geom geometry[], buffer numeric DEFAULT 0.5, tolerance numeric DEFAULT 1e-9)
#### Arguments
| Name | Type | Description |
|------|------|-------------|
| geom | geometry[] | Array of points's geometries |
| buffer | numeric | enlargment ratio for the envelope area used for the restraints|
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| tolerance | numeric | Delaunay tolerance, optional |
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### Returns
| Column Name | Type | Description |
|-------------|------|-------------|
| geom | geometry collection | Collection of polygons of the Voronoi cells|
#### Example Usage
```sql
WITH a AS (
SELECT
ARRAY[ST_GeomFromText('POINT(2.1744 41.403)'),ST_GeomFromText('POINT(2.1228 41.380)'),ST_GeomFromText('POINT(2.1511 41.374)'),ST_GeomFromText('POINT(2.1528 41.413)'),ST_GeomFromText('POINT(2.165 41.391)'),ST_GeomFromText('POINT(2.1498 41.371)'),ST_GeomFromText('POINT(2.1533 41.368)'),ST_GeomFromText('POINT(2.131386 41.41399)')] AS geomin
)
SELECT
CDB_voronoi(geomin, 0.2, 1e-9) as result
FROM a;
```
