13 geopandas

Adding a GeoPandas GeoDataFrame to the map with a single line of code

Uncomment the following line to install leafmap if needed. You can also use conda to create a new environment to install geopandas and leafmap.

conda create geo -n python=3.8
conda activate geo
conda install geopandas
conda install mamba -c conda-forge
mamba install leafmap -c conda-forge

In [1]:

# !pip install geopandas
# !pip install leafmap

# !pip install geopandas # !pip install leafmap

In [2]:

import leafmap
import geopandas as gpd

import leafmap import geopandas as gpd

In [3]:

# leafmap.update_package()

# leafmap.update_package()

Use GeoPandas to read a GeoJSON from an HTTP URL and return it as a GeoDataFrame.

Sample data: https://github.com/giswqs/leafmap/raw/master/examples/data/cable-geo.geojson

In [4]:

gdf = gpd.read_file(
    "https://github.com/giswqs/leafmap/raw/master/examples/data/cable-geo.geojson"
)

gdf = gpd.read_file( "https://github.com/giswqs/leafmap/raw/master/examples/data/cable-geo.geojson" )

---------------------------------------------------------------------------
HTTPError                                 Traceback (most recent call last)
Input In [4], in <cell line: 1>()
----> 1 gdf = gpd.read_file(
      2     "https://github.com/giswqs/leafmap/raw/master/examples/data/cable-geo.geojson"
      3 )

File ~/.local/lib/python3.9/site-packages/geopandas/io/file.py:170, in _read_file(filename, bbox, mask, rows, **kwargs)
    167 filename = _expand_user(filename)
    169 if _is_url(filename):
--> 170     req = _urlopen(filename)
    171     path_or_bytes = req.read()
    172     reader = fiona.BytesCollection

File /opt/hostedtoolcache/Python/3.9.10/x64/lib/python3.9/urllib/request.py:214, in urlopen(url, data, timeout, cafile, capath, cadefault, context)
    212 else:
    213     opener = _opener
--> 214 return opener.open(url, data, timeout)

File /opt/hostedtoolcache/Python/3.9.10/x64/lib/python3.9/urllib/request.py:523, in OpenerDirector.open(self, fullurl, data, timeout)
    521 for processor in self.process_response.get(protocol, []):
    522     meth = getattr(processor, meth_name)
--> 523     response = meth(req, response)
    525 return response

File /opt/hostedtoolcache/Python/3.9.10/x64/lib/python3.9/urllib/request.py:632, in HTTPErrorProcessor.http_response(self, request, response)
    629 # According to RFC 2616, "2xx" code indicates that the client's
    630 # request was successfully received, understood, and accepted.
    631 if not (200 <= code < 300):
--> 632     response = self.parent.error(
    633         'http', request, response, code, msg, hdrs)
    635 return response

File /opt/hostedtoolcache/Python/3.9.10/x64/lib/python3.9/urllib/request.py:561, in OpenerDirector.error(self, proto, *args)
    559 if http_err:
    560     args = (dict, 'default', 'http_error_default') + orig_args
--> 561     return self._call_chain(*args)

File /opt/hostedtoolcache/Python/3.9.10/x64/lib/python3.9/urllib/request.py:494, in OpenerDirector._call_chain(self, chain, kind, meth_name, *args)
    492 for handler in handlers:
    493     func = getattr(handler, meth_name)
--> 494     result = func(*args)
    495     if result is not None:
    496         return result

File /opt/hostedtoolcache/Python/3.9.10/x64/lib/python3.9/urllib/request.py:641, in HTTPDefaultErrorHandler.http_error_default(self, req, fp, code, msg, hdrs)
    640 def http_error_default(self, req, fp, code, msg, hdrs):
--> 641     raise HTTPError(req.full_url, code, msg, hdrs, fp)

HTTPError: HTTP Error 404: Not Found

Add a GeoDataFrame to the map.

In [5]:

m = leafmap.Map()
m.add_gdf(gdf, layer_name="Cable lines")
m

m = leafmap.Map() m.add_gdf(gdf, layer_name="Cable lines") m

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Input In [5], in <cell line: 2>()
      1 m = leafmap.Map()
----> 2 m.add_gdf(gdf, layer_name="Cable lines")
      3 m

NameError: name 'gdf' is not defined

The following example requires the ipyleaflet plotting backend.

In [6]:

import leafmap.leafmap as leafmap  # for ipyleaflet only

import leafmap.leafmap as leafmap # for ipyleaflet only

Read the GeoPandas sample dataset as a GeoDataFrame.

In [7]:

path_to_data = gpd.datasets.get_path("nybb")
gdf = gpd.read_file(path_to_data)
gdf

path_to_data = gpd.datasets.get_path("nybb") gdf = gpd.read_file(path_to_data) gdf

Out[7]:

	BoroCode	BoroName	Shape_Leng	Shape_Area	geometry
0	5	Staten Island	330470.010332	1.623820e+09	MULTIPOLYGON (((970217.022 145643.332, 970227....
1	4	Queens	896344.047763	3.045213e+09	MULTIPOLYGON (((1029606.077 156073.814, 102957...
2	3	Brooklyn	741080.523166	1.937479e+09	MULTIPOLYGON (((1021176.479 151374.797, 102100...
3	1	Manhattan	359299.096471	6.364715e+08	MULTIPOLYGON (((981219.056 188655.316, 980940....
4	2	Bronx	464392.991824	1.186925e+09	MULTIPOLYGON (((1012821.806 229228.265, 101278...

Convert the GeoDataFrame to GeoJSON. Users can then use add_geojson() to add the GeoJSON to the map. Alternatively, users can directly use the add_gdf() function to add a GeoDataFrame to the map. Note you when hovering the mouse over the layer, an information box is shown at the lower right corner of the map. This feature is only available for the ipyleaflet plotting backend.

In [8]:

geojson = leafmap.gdf_to_geojson(gdf, epsg="4326")
# geojson

geojson = leafmap.gdf_to_geojson(gdf, epsg="4326") # geojson

One can provide a list of colors (fill_colors) to randomly fill the polygons.

In [9]:

m = leafmap.Map()
m.add_gdf(gdf, layer_name="New York boroughs", fill_colors=["red", "green", "blue"])
m

m = leafmap.Map() m.add_gdf(gdf, layer_name="New York boroughs", fill_colors=["red", "green", "blue"]) m

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Last update: 2022-03-14