geo_s2cell_neighbors()
Applies to: ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel
Calculates S2 cell neighbors.
Read more about S2 cell hierarchy.
Syntax
geo_s2cell_neighbors(s2cell)
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| s2cell | string |
✔️ | S2 cell token value as it was calculated by geo_point_to_s2cell(). The S2 cell token maximum string length is 16 characters. |
Returns
An array of S2 cell neighbors. If the S2 Cell is invalid, the query produces a null result.
Note
S2 Cell edges are spherical geodesics.
Examples
The following example calculates S2 cell neighbors.
print neighbors = geo_s2cell_neighbors('89c259')
Output
| neighbors |
|---|
| ["89c25d","89c2f9","89c251","89c257","89c25f","89c25b","89c2f7","89c2f5"] |
The following example calculates an array of input S2 cell with its neighbors.
let s2cell = '89c259';
print cells = array_concat(pack_array(s2cell), geo_s2cell_neighbors(s2cell))
Output
| cells |
|---|
| ["89c259","89c25d","89c2f9","89c251","89c257","89c25f","89c25b","89c2f7","89c2f5"] |
The following example calculates S2 cells polygons GeoJSON geometry collection.
let s2cell = '89c259';
print cells = array_concat(pack_array(s2cell), geo_s2cell_neighbors(s2cell))
| mv-expand cells to typeof(string)
| project polygons = geo_s2cell_to_polygon(cells)
| summarize arr = make_list(polygons)
| project geojson = bag_pack("type", "Feature","geometry", bag_pack("type", "GeometryCollection", "geometries", arr), "properties", bag_pack("name", "polygons"))
Output
| geojson |
|---|
| {"type": "Feature","geometry": {"type": "GeometryCollection","geometries": [ {"type": "Polygon","coordinates": [[[ -74.030012249838478, 40.8012684339439],[ -74.030012249838478, 40.7222262918358],[ -73.935982114337421, 40.708880489804564],[ -73.935982114337421, 40.787917134506841],[ -74.030012249838478, 40.8012684339439]]]}, {"type": "Polygon","coordinates": [[[ -73.935982114337421, 40.708880489804564],[ -73.935982114337421, 40.629736433321796],[ -73.841906340776248, 40.616308079144915],[ -73.841906340776248, 40.695446474556284],[ -73.935982114337421, 40.708880489804564]]]}, {"type": "Polygon","coordinates": [[[ -74.1239959854733, 40.893471289549765],[ -74.1239959854733, 40.814531536204242],[ -74.030012249838478, 40.8012684339439],[ -74.030012249838478, 40.880202851376716],[ -74.1239959854733, 40.893471289549765]]]}, {"type": "Polygon","coordinates": [[[ -74.1239959854733, 40.735483949993387],[ -74.1239959854733, 40.656328734184143],[ -74.030012249838478, 40.643076628676461],[ -74.030012249838478, 40.7222262918358],[ -74.1239959854733, 40.735483949993387]]]}, {"type": "Polygon","coordinates": [[[ -74.1239959854733, 40.814531536204242],[ -74.1239959854733, 40.735483949993387],[ -74.030012249838478, 40.7222262918358],[ -74.030012249838478, 40.8012684339439],[ -74.1239959854733, 40.814531536204242]]]}, {"type": "Polygon","coordinates": [[[ -73.935982114337421, 40.787917134506841],[ -73.935982114337421, 40.708880489804564],[ -73.841906340776248, 40.695446474556284],[ -73.841906340776248, 40.774477568182071],[ -73.935982114337421, 40.787917134506841]]]}, {"type": "Polygon","coordinates": [[[ -74.030012249838478, 40.7222262918358],[ -74.030012249838478, 40.643076628676461],[ -73.935982114337421, 40.629736433321796],[ -73.935982114337421, 40.708880489804564],[ -74.030012249838478, 40.7222262918358]]]}, {"type": "Polygon","coordinates": [[[ -74.030012249838478, 40.880202851376716],[ -74.030012249838478, 40.8012684339439],[ -73.935982114337421, 40.787917134506841],[ -73.935982114337421, 40.866846163445771],[ -74.030012249838478, 40.880202851376716]]]}, {"type": "Polygon","coordinates": [[[ -73.935982114337421, 40.866846163445771],[ -73.935982114337421, 40.787917134506841],[ -73.841906340776248, 40.774477568182071],[ -73.841906340776248, 40.853401155678846],[ -73.935982114337421, 40.866846163445771]]]}]}, "properties": {"name": "polygons"}} |
The following example calculates polygon unions that represent S2 cell and its neighbors.
let s2cell = '89c259';
print cells = array_concat(pack_array(s2cell), geo_s2cell_neighbors(s2cell))
| mv-expand cells to typeof(string)
| project polygons = geo_s2cell_to_polygon(cells)
| summarize arr = make_list(polygons)
| project polygon = geo_union_polygons_array(arr)
Output
| polygon |
|---|
| {"type": "Polygon","coordinates": [[[-73.841906340776248,40.695446474556284],[-73.841906340776248,40.774477568182071],[-73.841906340776248,40.853401155678846],[-73.935982114337421,40.866846163445771],[-74.030012249838478,40.880202851376716],[-74.1239959854733,40.893471289549758],[-74.1239959854733,40.814531536204242],[-74.1239959854733,40.735483949993387],[-74.1239959854733,40.656328734184143],[-74.030012249838478,40.643076628676461],[-73.935982114337421,40.629736433321796],[-73.841906340776248,40.616308079144915],[-73.841906340776248,40.695446474556284]]]} |
The following example returns true because of the invalid S2 Cell token input.
print invalid = isnull(geo_s2cell_neighbors('a'))
Output
| invalid |
|---|
| 1 |