ST_Dimension takes a geometry column and returns an integer column. The output column represents the dimensionality of the input geometry. Points and multipoints have a dimension of 0, lines 1, and polygons 2.
| Function | Syntax |
|---|---|
| Python | dimension(geometry) |
| SQL | ST |
| Scala | dimension(geometry) |
For more details, go to the GeoAnalytics Engine API reference for dimension.
This function implements the OpenGIS Simple Features Implementation Specification for SQL 1.2.1.
Examples
from geoanalytics.sql import functions as ST, Linestring, MultiPoint, Point, Polygon
data = [
("point", "POINT (10 30)"),
("multipoint", "MULTIPOINT (0 0, 5 5, 0 5)"),
("linestring", "LINESTRING (15 15, 10 15, 12 2)"),
("polygon", "POLYGON ((20 30, 18 28, 22 35, 40 20))")
]
df = spark.createDataFrame(data, ["type", "wkt"])\
.withColumn("geometry", ST.geom_from_text("wkt"))
df.select("type", ST.dimension("geometry").alias("dimension")).show()Result
+----------+---------+
| type|dimension|
+----------+---------+
| point| 0|
|multipoint| 0|
|linestring| 1|
| polygon| 2|
+----------+---------+Version table
| Release | Notes |
|---|---|
1.0.0 | Python and SQL functions introduced |
1.5.0 | Scala function introduced |