ST_Envelope

ST_Envelope takes a geometry column and returns a polygon column. The function returns an envelope for each geometry in the input column, where an envelope is the smallest rectangle that encompasses the input geometry and aligns to the x-axis and y-axis. To find the smallest rectangle that encompasses a geometry but is not axis-aligned, use ST_MinBoundingBox. If the input geometry is a single point, the function will create a degenerate polygon at the location of the point.

Function	Syntax
Python	`envelope(geometry)`
SQL	`ST_Envelope(geometry)`

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

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("envelope", ST.envelope("geometry"))

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

Plotting example for ST_Envelope — Plotted result for ST_Envelope.

Version table

Release	Notes
1.0.0	Function introduced

ST_Envelope

Examples

Version table

Related topics