ST_PolyFromBinary takes a binary column and returns a polygon column.
The input binary column must contain the
well-known binary (WKB)
representation of polygon geometries. You can optionally specify a spatial reference for the result polygon column.
The sr parameter value must be a valid SRID or WKT string.
If a polygon cannot be created from the input binary the function will return null.
| Function | Syntax |
|---|---|
| Python | poly |
| SQL | ST |
| Scala | poly |
For more details, go to the GeoAnalytics Engine API reference for poly_from_binary.
This function implements the OpenGIS Simple Features Implementation Specification for SQL 1.2.1.
Examples
from geoanalytics.sql import functions as ST
polygon_binary= bytearray(b'\x01\x03\x00\x00\x00\x01\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x004@\x00\x00\x00\x00\x00\x00>@\x00\x00\x00\x00\x00\x006@\x00\x00\x00\x00\x00\x80A@\x00\x00\x00\x00\x00\x002@\x00\x00\x00\x00\x00\x00<@\x00\x00\x00\x00\x00\x004@\x00\x00\x00\x00\x00\x00>@')
df = spark.createDataFrame([(polygon_binary,)], ["wkb"])
df.select(ST.poly_from_binary("wkb", sr=4326).alias("poly_from_binary")).show(truncate=False)Result
+---------------------------------------------+
|poly_from_binary |
+---------------------------------------------+
|{"rings":[[[20,30],[18,28],[22,35],[20,30]]]}|
+---------------------------------------------+Version table
| Release | Notes |
|---|---|
1.0.0 | Python and SQL functions introduced |
1.5.0 | Scala function introduced |