Returns the gridding level of a geographic grid.
Syntax
integer ST_Level(geomgrid gridcode);
integer[] ST_Level(geomgrid[] gridcode);
integer ST_Level(h3grid gridcode);Parameters
| Parameter | Description |
|---|---|
gridcode | The geographic grid object. Accepts a single geomgrid, an array of geomgrid objects (geomgrid[]), or a single h3grid. |
Description
ST_Level returns the level of a geographic grid object. The return type depends on the input:
Single `geomgrid`: returns an
integerrepresenting the grid level.`geomgrid[]` array: returns an
integer[]array representing the level range across all grids in the array.Single `h3grid`: returns an
integerrepresenting the H3 resolution level.
Examples
Get the level of a single geomgrid
SELECT st_level(ST_GridFromText('GZ0026206440'));
st_level
----------
10Get the level range of a geomgrid array
SELECT st_level(st_as3dgrid('srid=4490;GEOMETRYCOLLECTION Z (MULTIPOLYGON Z (((116 39 5000,116.12 39 5000,116.12 39.09 5000,116 39.09 5000,116 39 5000),
(116.024 39.018 5000,116.024 39.045 5000,116.06 39.045 5000,116.06 39.018 5000,116.024 39.018 5000))),
POINT Z (116 39 5000),MULTILINESTRING Z ((116 39 5000,116.024 39 5000),(116.012 39.009 5000,116.024 39.018 5000)),
POLYHEDRALSURFACE Z (((116 39 0,116 39 1000,116 39.009 0,116 39 0)),((116 39 0,116 39.009 0,116.012 39 0,116 39 0)),
((116 39 0,116.012 39 0,116 39 1000,116 39 0)),((116.012 39 0,116 39.009 0,116 39 1000,116.012 39 0))))'::geometry,
20,true));
st_level
----------
{19,20}Get the level of an H3 grid
-- H3 encoding
SELECT st_level(st_h3frombinary('\x010100ffff9f6826a18408'));
st_level
----------
8See also
| Function | Description |
|---|---|
ST_GridFromText | Creates a geomgrid object from a grid code string |
st_as3dgrid | Converts a 3D geometry to a geomgrid array |
st_h3frombinary | Creates an h3grid object from a binary H3 index |