ST_DWithin takes two geometry columns and a numeric distance value and returns a boolean column. The function returns
True if the two geometries are spatially within the given distance; otherwise, it returns
False. For multipoints,
lines, and polygons, the distance is calculated from the nearest point between the geometries. You can optionally
provide a boolean value that determines if geodesic distances will be used by the function. Planar distances will be
used by default.
When using planar calculations, the distance value is specified in the same units as the input geometry.
geodesic is set to
True, the distance value is specified in meters. In both cases, the value can be set
using a numeric column or a single value.
If the two geometry columns are in different spatial references, the function will automatically transform the second geometry into the spatial reference of the first.
When using geodesic distances, the first geometry column must have a spatial reference set. To learn more see Coordinate systems and transformations.
This function may use an optimized spatial join to calculate results.
For more details, go to the GeoAnalytics Engine API reference for dwithin.
from geoanalytics.sql import functions as ST, Point data = [ (Point(-176, -15), Point(-176, -15)), (Point(-176, -15), Point(-176, -20)), (Point(-176, -15), Point(-175, -15)) ] df = spark.createDataFrame(data, ["point1", "point2"]) df.select(ST.dwithin("point1", "point2", 3.0).alias("dwithin")).show()
+-------+ |dwithin| +-------+ | true| | false| | true| +-------+