Create Multipolygon¶

This example shows to create, visualize and store a multipolygon using GeoKit. Similar to a multiline object it allows to store multiple polygons as a single geometry object.

Import required packages¶

In [1]:

import geokit.core.geom
import geokit.core.vector
import geokit.core.srs

import geokit.core.geom import geokit.core.vector import geokit.core.srs

Create Polygon¶

In [2]:

# Create a Polygon geometry from a list of coordinate tuples.

# Define a projection for the Aachen area
aachen_centered_srs = geokit.core.srs.centeredLAEA(6.083, 50.775)

# Create 2 polygons from an ordered list of xy-coordinate tuples
aachen_polygon_1 = geokit.core.geom.polygon(
    [
        (0, 0),
        (40000, 0),
        (40000, 30000),
        (20000, 50000),
        (0, 30000),
        (0, 0),
    ],
    srs=aachen_centered_srs,
)

aachen_polygon_2 = geokit.core.geom.polygon(
    [
        (40000, 0),
        (80000, 0),
        (80000, 30000),
        (60000, 50000),
        (40000, 30000),
        (40000, 0),
    ],
    srs=aachen_centered_srs,
)

# combine polygons into a multipolygon
polys = [aachen_polygon_1, aachen_polygon_2]
multi_poly = geokit.core.geom.flatten(polys)

# Create a Polygon geometry from a list of coordinate tuples. # Define a projection for the Aachen area aachen_centered_srs = geokit.core.srs.centeredLAEA(6.083, 50.775) # Create 2 polygons from an ordered list of xy-coordinate tuples aachen_polygon_1 = geokit.core.geom.polygon( [ (0, 0), (40000, 0), (40000, 30000), (20000, 50000), (0, 30000), (0, 0), ], srs=aachen_centered_srs, ) aachen_polygon_2 = geokit.core.geom.polygon( [ (40000, 0), (80000, 0), (80000, 30000), (60000, 50000), (40000, 30000), (40000, 0), ], srs=aachen_centered_srs, ) # combine polygons into a multipolygon polys = [aachen_polygon_1, aachen_polygon_2] multi_poly = geokit.core.geom.flatten(polys)

Visualize Polygon¶

In [3]:

ax_handle = geokit.core.geom.drawGeoms(
    geoms=multi_poly,
    figsize=(4, 4),
)

ax_handle = geokit.core.geom.drawGeoms( geoms=multi_poly, figsize=(4, 4), )

Store Multipolygon as Vector File¶

In [4]:

# Simple vector creation
geokit.core.vector.createVector(geoms=multi_poly, output="example_multi_polygon.shp")

# Simple vector creation geokit.core.vector.createVector(geoms=multi_poly, output="example_multi_polygon.shp")

Out[4]:

'/home/docs/checkouts/readthedocs.org/user_builds/geokit/checkouts/latest/docs/Examples/_03_geometries/_01_create_geometries/example_multi_polygon.shp'