ST_PointOnSurface

ST_PointOnSurface takes a geometry column and returns a point column. The function returns a point that lies on the surface of linestring or polygon geometries.

Function	Syntax
Python	`point_on_surface(geometry)`
SQL	`ST_PointOnSurface(geometry)`

For more details, go to the GeoAnalytics Engine API reference for point_on_surface.

This function implements the OpenGIS Simple Features Implementation Specification for SQL 1.2.1.

Examples

Python

SQL

Use dark colors for code blocksCopy
from geoanalytics.sql import functions as ST

data = [
    ("POINT (10 30)",),
    ("MULTIPOINT (0 0, 5 5, 0 5)", ),
    ("LINESTRING (15 15, 10 15, 12 2)", ),
    ("POLYGON ((20 30, 18 28, 22 35, 40 20))", )
]

df = spark.createDataFrame(data, ["wkt"])\
          .select(ST.geom_from_text("wkt").alias("geometry"))

df = df.withColumn("point_on_surface", ST.point_on_surface("geometry"))

ax = df.st.plot("geometry", facecolor="none", edgecolor="red")
df.st.plot("point_on_surface", ax=ax, facecolor="none", edgecolor="blue")

Plotting example for ST_PointOnSurface — Plotted result for ST_PointOnSurface.

Version table

Release	Notes
1.0.0	Function introduced

ST_PointOnSurface

Examples

Version table

Related topics