Work with GeoPandas and Shapely

Danger

Sedona Python currently only works with Shapely 1.x. If you use GeoPandas, please use <= GeoPandas 0.11.1. GeoPandas > 0.11.1 will automatically install Shapely 2.0. If you use Shapely, please use <= 1.8.4.

Interoperate with GeoPandas

Sedona Python has implemented serializers and deserializers which allows to convert Sedona Geometry objects into Shapely BaseGeometry objects. Based on that it is possible to load the data with geopandas from file (look at Fiona possible drivers) and create Spark DataFrame based on GeoDataFrame object.

From GeoPandas to Sedona DataFrame

Loading the data from shapefile using geopandas read_file method and create Spark DataFrame based on GeoDataFrame:

import geopandas as gpd
from sedona.spark import *

config = SedonaContext.builder().\
      getOrCreate()

sedona = SedonaContext.create(config)

gdf = gpd.read_file("gis_osm_pois_free_1.shp")

sedona.createDataFrame(
  gdf
).show()

This query will show the following outputs:

+---------+----+-----------+--------------------+--------------------+
|   osm_id|code|     fclass|                name|            geometry|
+---------+----+-----------+--------------------+--------------------+
| 26860257|2422|  camp_site|            de Kroon|POINT (15.3393145...|
| 26860294|2406|     chalet|      Leśne Ustronie|POINT (14.8709625...|
| 29947493|2402|      motel|                null|POINT (15.0946636...|
| 29947498|2602|        atm|                null|POINT (15.0732014...|
| 29947499|2401|      hotel|                null|POINT (15.0696777...|
| 29947505|2401|      hotel|                null|POINT (15.0155749...|
+---------+----+-----------+--------------------+--------------------+

From Sedona DataFrame to GeoPandas

Reading data with Spark and converting to GeoPandas

import geopandas as gpd
from sedona.spark import *

config = SedonaContext.builder().
    getOrCreate()

sedona = SedonaContext.create(config)

counties = sedona.\
    read.\
    option("delimiter", "|").\
    option("header", "true").\
    csv("counties.csv")

counties.createOrReplaceTempView("county")

counties_geom = sedona.sql(
    "SELECT *, st_geomFromWKT(geom) as geometry from county"
)

df = counties_geom.toPandas()
gdf = gpd.GeoDataFrame(df, geometry="geometry")

gdf.plot(
    figsize=(10, 8),
    column="value",
    legend=True,
    cmap='YlOrBr',
    scheme='quantiles',
    edgecolor='lightgray'
)

Interoperate with shapely objects

Supported Shapely objects

shapely object	Available
Point
MultiPoint
LineString
MultiLinestring
Polygon
MultiPolygon

To create Spark DataFrame based on mentioned Geometry types, please use GeometryType from sedona.sql.types module. Converting works for list or tuple with shapely objects.

Schema for target table with integer id and geometry type can be defined as follow:

from pyspark.sql.types import IntegerType, StructField, StructType

from sedona.spark import *

schema = StructType(
    [
        StructField("id", IntegerType(), False),
        StructField("geom", GeometryType(), False)
    ]
)

Also Spark DataFrame with geometry type can be converted to list of shapely objects with collect method.

Point example

from shapely.geometry import Point

data = [
    [1, Point(21.0, 52.0)],
    [1, Point(23.0, 42.0)],
    [1, Point(26.0, 32.0)]
]


gdf = sedona.createDataFrame(
    data,
    schema
)

gdf.show()

+---+-------------+
| id|         geom|
+---+-------------+
|  1|POINT (21 52)|
|  1|POINT (23 42)|
|  1|POINT (26 32)|
+---+-------------+

gdf.printSchema()

root
 |-- id: integer (nullable = false)
 |-- geom: geometry (nullable = false)

MultiPoint example

from shapely.geometry import MultiPoint

data = [
    [1, MultiPoint([[19.511463, 51.765158], [19.446408, 51.779752]])]
]

gdf = sedona.createDataFrame(
    data,
    schema
).show(1, False)

+---+---------------------------------------------------------+
|id |geom                                                     |
+---+---------------------------------------------------------+
|1  |MULTIPOINT ((19.511463 51.765158), (19.446408 51.779752))|
+---+---------------------------------------------------------+

LineString example

from shapely.geometry import LineString

line = [(40, 40), (30, 30), (40, 20), (30, 10)]

data = [
    [1, LineString(line)]
]

gdf = sedona.createDataFrame(
    data,
    schema
)

gdf.show(1, False)

+---+--------------------------------+
|id |geom                            |
+---+--------------------------------+
|1  |LINESTRING (10 10, 20 20, 10 40)|
+---+--------------------------------+

MultiLineString example

from shapely.geometry import MultiLineString

line1 = [(10, 10), (20, 20), (10, 40)]
line2 = [(40, 40), (30, 30), (40, 20), (30, 10)]

data = [
    [1, MultiLineString([line1, line2])]
]

gdf = sedona.createDataFrame(
    data,
    schema
)

gdf.show(1, False)

+---+---------------------------------------------------------------------+
|id |geom                                                                 |
+---+---------------------------------------------------------------------+
|1  |MULTILINESTRING ((10 10, 20 20, 10 40), (40 40, 30 30, 40 20, 30 10))|
+---+---------------------------------------------------------------------+

Polygon example

from shapely.geometry import Polygon

polygon = Polygon(
    [
         [19.51121, 51.76426],
         [19.51056, 51.76583],
         [19.51216, 51.76599],
         [19.51280, 51.76448],
         [19.51121, 51.76426]
    ]
)

data = [
    [1, polygon]
]

gdf = sedona.createDataFrame(
    data,
    schema
)

gdf.show(1, False)

+---+--------------------------------------------------------------------------------------------------------+
|id |geom                                                                                                    |
+---+--------------------------------------------------------------------------------------------------------+
|1  |POLYGON ((19.51121 51.76426, 19.51056 51.76583, 19.51216 51.76599, 19.5128 51.76448, 19.51121 51.76426))|
+---+--------------------------------------------------------------------------------------------------------+

MultiPolygon example

from shapely.geometry import MultiPolygon

exterior_p1 = [(0, 0), (0, 2), (2, 2), (2, 0), (0, 0)]
interior_p1 = [(1, 1), (1, 1.5), (1.5, 1.5), (1.5, 1), (1, 1)]

exterior_p2 = [(0, 0), (1, 0), (1, 1), (0, 1), (0, 0)]

polygons = [
    Polygon(exterior_p1, [interior_p1]),
    Polygon(exterior_p2)
]

data = [
    [1, MultiPolygon(polygons)]
]

gdf = sedona.createDataFrame(
    data,
    schema
)

gdf.show(1, False)

+---+----------------------------------------------------------------------------------------------------------+
|id |geom                                                                                                      |
+---+----------------------------------------------------------------------------------------------------------+
|1  |MULTIPOLYGON (((0 0, 0 2, 2 2, 2 0, 0 0), (1 1, 1.5 1, 1.5 1.5, 1 1.5, 1 1)), ((0 0, 0 1, 1 1, 1 0, 0 0)))|
+---+----------------------------------------------------------------------------------------------------------+

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Last update: June 6, 2023 07:38:32