Contents

Brexit

import geopandas
import topojson
import matplotlib.pyplot as plt

Local Authority District (LAD) geometries

The original geometries are downloaded from the Office of National Statistics through data.gov.uk and stored locally:

lads = geopandas.read_file('./Local_Authority_Districts_December_2016_'
                           'Generalised_Clipped_Boundaries_in_the_UK_WGS84/'
                           'Local_Authority_Districts_December_2016_'
                           'Generalised_Clipped_Boundaries_in_the_UK_WGS84.shp'
                          )

Topology simplification

To obtain a much more lightweight set of geometries, we simplify the layer, respecting its topology. First we build the topology:

topology = topojson.Topology(lads)

Then simplify it:

simple_uk = topology.toposimplify(.025)

Inspect the resulting geography:

simple_uk.to_gdf().plot()

<AxesSubplot:>
../../_images/brexit_cleaning_10_1.png

And we can write it to a GeoJSON file:

simple_uk.to_gdf().to_file('./local_authority_districts.geojson', driver="GeoJSON")