ST_Boundary takes a geometry column and returns a geometry column. The output column contains the topological boundary of the given geometry. The function will return a linestring if the input is a polygon and a multipoint if the input is a linestring. Point and multipoint inputs are not supported.
| Function | Syntax |
|---|---|
| Python | boundary(geometry) |
| SQL | ST |
| Scala | boundary(geometry) |
For more details, go to the GeoAnalytics for Microsoft Fabric API reference for boundary.
This function implements the OpenGIS Simple Features Implementation Specification for SQL 1.1.
Examples
from geoanalytics_fabric.sql import functions as ST
data = [
("POINT (10, 30)",),
("MULTIPOINT (0 0, 10 10, 20 20)", ),
("LINESTRING (0 0, 10 10, 20 20)", ),
("POLYGON ((0 0, 5 5, 10 0, 20 10))", )
]
df = spark.createDataFrame(data, ["wkt"])\
.select(ST.geom_from_text("wkt").alias("geometry"))
df.select(ST.boundary("geometry").alias("boundary")).show(truncate=False)Result
+----------------------------------------------+
|boundary |
+----------------------------------------------+
|NULL |
|NULL |
|{"points":[[0,0],[20,20]]} |
|{"paths":[[[0,0],[20,10],[10,0],[5,5],[0,0]]]}|
+----------------------------------------------+Version table
| Release | Notes |
|---|---|
1.0.0-beta | Python, SQL, and Scala functions introduced |