Working with coordinate systems in GeoPandas

Lavorare con i dati geospaziali in Python

Joris Van den Bossche

Open source software developer and teacher, GeoPandas maintainer

CRS information in GeoPandas

The .crs attribute of a GeoDataFrame/GeoSeries:

import geopandas
gdf = geopandas.read_file("countries.shp")
print(gdf.crs)

{'init': 'epsg:4326'}

gdf_noCRS = geopandas.read_file("countries_noCRS.shp")
print(gdf_noCRS.crs)

{}

Add CRS information to crs:

# Option 1
gdf.crs = {'init': 'epsg:4326'}

# Option 2
gdf.crs = {'proj': 'longlat', 'datum': 'WGS84', 'no_defs': True}

import geopandas
gdf = geopandas.read_file("countries_web_mercator.shp")
print(gdf.crs)

{'init': 'epsg:3857', 'no_defs': True}

The to_crs() method:

# Option 1
gdf2 = gdf.to_crs({'proj': 'longlat', 'datum': 'WGS84', 'no_defs': True})

# Option 2
gdf2 = gdf.to_crs(epsg=4326)

1) Sources with a different CRS

df1 = geopandas.read_file(...)
df2 = geopandas.read_file(...)

df2 = df2.to_crs(df1.crs)

1) Sources with a different CRS

2) Mapping (distortion of shape and distances)

1) Sources with a different CRS

2) Mapping (distortion of shape and distances)

3) Distance / area based calculations

Tips:

Useful sites:

Useful sites:

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