Geopandas Intro

Getting Started with GeoPandas

References:

• https://geopandas.org/getting_started/introduction.html
• https://geopandas.org/docs/user_guide/io.html
• https://geodemo.gishub.org
• https://geemap.org

Installation¶

conda create -n geo python=3.8
conda activate geo
conda install geopandas
conda install geodemo matplotlib descartes -c conda-forge

Import libraries¶

In [1]:

import geodemo
import geopandas as gpd

import geodemo import geopandas as gpd

---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Cell In[1], line 1
----> 1 import geodemo
      2 import geopandas as gpd

ModuleNotFoundError: No module named 'geodemo'

Reading files¶

In [2]:

url = "https://raw.githubusercontent.com/giswqs/geodemo/master/examples/data/nyc_neighborhoods.geojson"

url = "https://raw.githubusercontent.com/giswqs/geodemo/master/examples/data/nyc_neighborhoods.geojson"

In [3]:

gdf = gpd.read_file(url)

gdf = gpd.read_file(url)

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[3], line 1
----> 1 gdf = gpd.read_file(url)

NameError: name 'gpd' is not defined

In [4]:

gdf

gdf

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[4], line 1
----> 1 gdf

NameError: name 'gdf' is not defined

In [5]:

gdf.crs

gdf.crs

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[5], line 1
----> 1 gdf.crs

NameError: name 'gdf' is not defined

Writing files¶

In [6]:

gdf.to_file("data/nyc_streets.geojson", driver="GeoJSON")

gdf.to_file("data/nyc_streets.geojson", driver="GeoJSON")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[6], line 1
----> 1 gdf.to_file("data/nyc_streets.geojson", driver="GeoJSON")

NameError: name 'gdf' is not defined

Measuring area¶

In [7]:

gdf = gdf.set_index("NAME")

gdf = gdf.set_index("NAME")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[7], line 1
----> 1 gdf = gdf.set_index("NAME")

NameError: name 'gdf' is not defined

In [8]:

gdf["area"] = gdf.area
gdf["area"]

gdf["area"] = gdf.area gdf["area"]

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[8], line 1
----> 1 gdf["area"] = gdf.area
      2 gdf["area"]

NameError: name 'gdf' is not defined

Getting polygon boundary¶

In [9]:

gdf['boundary'] = gdf.boundary
gdf['boundary']

gdf['boundary'] = gdf.boundary gdf['boundary']

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[9], line 1
----> 1 gdf['boundary'] = gdf.boundary
      2 gdf['boundary']

NameError: name 'gdf' is not defined

Getting polygon centroid¶

In [10]:

gdf['centroid'] = gdf.centroid
gdf['centroid']

gdf['centroid'] = gdf.centroid gdf['centroid']

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[10], line 1
----> 1 gdf['centroid'] = gdf.centroid
      2 gdf['centroid']

NameError: name 'gdf' is not defined

Making maps¶

In [11]:

gdf.plot()

gdf.plot()

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[11], line 1
----> 1 gdf.plot()

NameError: name 'gdf' is not defined

In [12]:

gdf.plot("area", legend=True, figsize=(10, 8))

gdf.plot("area", legend=True, figsize=(10, 8))

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[12], line 1
----> 1 gdf.plot("area", legend=True, figsize=(10, 8))

NameError: name 'gdf' is not defined

In [13]:

gdf = gdf.set_geometry("centroid")
gdf.plot("area", legend=True,figsize=(10, 8))

gdf = gdf.set_geometry("centroid") gdf.plot("area", legend=True,figsize=(10, 8))

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[13], line 1
----> 1 gdf = gdf.set_geometry("centroid")
      2 gdf.plot("area", legend=True,figsize=(10, 8))

NameError: name 'gdf' is not defined

In [14]:

ax = gdf["geometry"].plot(figsize=(10, 8))
gdf["centroid"].plot(ax=ax, color="black")

ax = gdf["geometry"].plot(figsize=(10, 8)) gdf["centroid"].plot(ax=ax, color="black")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[14], line 1
----> 1 ax = gdf["geometry"].plot(figsize=(10, 8))
      2 gdf["centroid"].plot(ax=ax, color="black")

NameError: name 'gdf' is not defined

In [15]:

gdf = gdf.set_geometry("geometry")

gdf = gdf.set_geometry("geometry")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[15], line 1
----> 1 gdf = gdf.set_geometry("geometry")

NameError: name 'gdf' is not defined

Reprojecting data¶

In [16]:

url = "https://raw.githubusercontent.com/giswqs/geodemo/master/examples/data/nyc_neighborhoods.geojson"

url = "https://raw.githubusercontent.com/giswqs/geodemo/master/examples/data/nyc_neighborhoods.geojson"

In [17]:

gdf = gpd.read_file(url)

gdf = gpd.read_file(url)

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[17], line 1
----> 1 gdf = gpd.read_file(url)

NameError: name 'gpd' is not defined

In [18]:

gdf_crs = gdf.to_crs(epsg="4326")

gdf_crs = gdf.to_crs(epsg="4326")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[18], line 1
----> 1 gdf_crs = gdf.to_crs(epsg="4326")

NameError: name 'gdf' is not defined

In [19]:

gdf_crs

gdf_crs

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[19], line 1
----> 1 gdf_crs

NameError: name 'gdf_crs' is not defined

In [20]:

geojson = gdf_crs.__geo_interface__

geojson = gdf_crs.__geo_interface__

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[20], line 1
----> 1 geojson = gdf_crs.__geo_interface__

NameError: name 'gdf_crs' is not defined

Displaying data on an interactive map¶

In [21]:

m = geodemo.Map(center=[40.7341, -73.9113], zoom=10)
m

m = geodemo.Map(center=[40.7341, -73.9113], zoom=10) m

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[21], line 1
----> 1 m = geodemo.Map(center=[40.7341, -73.9113], zoom=10)
      2 m

NameError: name 'geodemo' is not defined

In [22]:

style = {
    "stroke": True,
    "color": "#000000",
    "weight": 2,
    "opacity": 1,
    "fill": True,
    "fillColor": "#0000ff",
    "fillOpacity": 0.4,
}

style = { "stroke": True, "color": "#000000", "weight": 2, "opacity": 1, "fill": True, "fillColor": "#0000ff", "fillOpacity": 0.4, }

In [23]:

m.add_geojson(geojson, style=style, layer_name="nyc neighborhoods")

m.add_geojson(geojson, style=style, layer_name="nyc neighborhoods")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[23], line 1
----> 1 m.add_geojson(geojson, style=style, layer_name="nyc neighborhoods")

NameError: name 'm' is not defined

In [24]:

url2 = "https://github.com/giswqs/geodemo/raw/master/examples/data/nyc_subway_stations.zip"

url2 = "https://github.com/giswqs/geodemo/raw/master/examples/data/nyc_subway_stations.zip"

In [25]:

gdf_subway = gpd.read_file(url2)

gdf_subway = gpd.read_file(url2)

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[25], line 1
----> 1 gdf_subway = gpd.read_file(url2)

NameError: name 'gpd' is not defined

In [26]:

gdf_subway_crs = gdf_subway.to_crs(epsg="4326")

gdf_subway_crs = gdf_subway.to_crs(epsg="4326")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[26], line 1
----> 1 gdf_subway_crs = gdf_subway.to_crs(epsg="4326")

NameError: name 'gdf_subway' is not defined

In [27]:

subway_geojson = gdf_subway_crs.__geo_interface__

subway_geojson = gdf_subway_crs.__geo_interface__

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[27], line 1
----> 1 subway_geojson = gdf_subway_crs.__geo_interface__

NameError: name 'gdf_subway_crs' is not defined

In [28]:

m.add_geojson(subway_geojson, layer_name="nyc subway stations")

m.add_geojson(subway_geojson, layer_name="nyc subway stations")

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[28], line 1
----> 1 m.add_geojson(subway_geojson, layer_name="nyc subway stations")

NameError: name 'm' is not defined