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2025-01-26 19:24:23 -08:00

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Python

import json
import warnings
import numpy as np
import pandas as pd
from pandas import DataFrame, Series
import shapely.errors
from shapely.geometry import mapping, shape
from shapely.geometry.base import BaseGeometry
import geopandas.io
from geopandas.array import GeometryArray, GeometryDtype, from_shapely, to_wkb, to_wkt
from geopandas.base import GeoPandasBase, is_geometry_type
from geopandas.explore import _explore
from geopandas.geoseries import GeoSeries
from ._compat import HAS_PYPROJ, PANDAS_GE_30
from ._decorator import doc
if PANDAS_GE_30:
from pandas.core.accessor import Accessor
else:
from pandas.core.accessor import CachedAccessor as Accessor
def _geodataframe_constructor_with_fallback(*args, **kwargs):
"""
A flexible constructor for GeoDataFrame._constructor, which falls back
to returning a DataFrame (if a certain operation does not preserve the
geometry column)
"""
df = GeoDataFrame(*args, **kwargs)
geometry_cols_mask = df.dtypes == "geometry"
if len(geometry_cols_mask) == 0 or geometry_cols_mask.sum() == 0:
df = pd.DataFrame(df)
return df
def _ensure_geometry(data, crs=None):
"""
Ensure the data is of geometry dtype or converted to it.
If input is a (Geo)Series, output is a GeoSeries, otherwise output
is GeometryArray.
If the input is a GeometryDtype with a set CRS, `crs` is ignored.
"""
if is_geometry_type(data):
if isinstance(data, Series):
data = GeoSeries(data)
if data.crs is None and crs is not None:
# Avoids caching issues/crs sharing issues
data = data.copy()
if isinstance(data, GeometryArray):
data.crs = crs
else:
data.array.crs = crs
return data
else:
if isinstance(data, Series):
out = from_shapely(np.asarray(data), crs=crs)
return GeoSeries(out, index=data.index, name=data.name)
else:
out = from_shapely(data, crs=crs)
return out
crs_mismatch_error = (
"CRS mismatch between CRS of the passed geometries "
"and 'crs'. Use 'GeoDataFrame.set_crs(crs, "
"allow_override=True)' to overwrite CRS or "
"'GeoDataFrame.to_crs(crs)' to reproject geometries. "
)
class GeoDataFrame(GeoPandasBase, DataFrame):
"""
A GeoDataFrame object is a pandas.DataFrame that has one or more columns
containing geometry. In addition to the standard DataFrame constructor arguments,
GeoDataFrame also accepts the following keyword arguments:
Parameters
----------
crs : value (optional)
Coordinate Reference System of the geometry objects. Can be anything accepted by
:meth:`pyproj.CRS.from_user_input() <pyproj.crs.CRS.from_user_input>`,
such as an authority string (eg "EPSG:4326") or a WKT string.
geometry : str or array-like (optional)
Value to use as the active geometry column.
If str, treated as column name to use. If array-like, it will be
added as new column named 'geometry' on the GeoDataFrame and set as the
active geometry column.
Note that if ``geometry`` is a (Geo)Series with a
name, the name will not be used, a column named "geometry" will still be
added. To preserve the name, you can use :meth:`~GeoDataFrame.rename_geometry`
to update the geometry column name.
Examples
--------
Constructing GeoDataFrame from a dictionary.
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d, crs="EPSG:4326")
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
Notice that the inferred dtype of 'geometry' columns is geometry.
>>> gdf.dtypes
col1 object
geometry geometry
dtype: object
Constructing GeoDataFrame from a pandas DataFrame with a column of WKT geometries:
>>> import pandas as pd
>>> d = {'col1': ['name1', 'name2'], 'wkt': ['POINT (1 2)', 'POINT (2 1)']}
>>> df = pd.DataFrame(d)
>>> gs = geopandas.GeoSeries.from_wkt(df['wkt'])
>>> gdf = geopandas.GeoDataFrame(df, geometry=gs, crs="EPSG:4326")
>>> gdf
col1 wkt geometry
0 name1 POINT (1 2) POINT (1 2)
1 name2 POINT (2 1) POINT (2 1)
See also
--------
GeoSeries : Series object designed to store shapely geometry objects
"""
_metadata = ["_geometry_column_name"]
_internal_names = DataFrame._internal_names + ["geometry"]
_internal_names_set = set(_internal_names)
_geometry_column_name = None
def __init__(self, data=None, *args, geometry=None, crs=None, **kwargs):
if (
kwargs.get("copy") is None
and isinstance(data, DataFrame)
and not isinstance(data, GeoDataFrame)
):
kwargs.update(copy=True)
super().__init__(data, *args, **kwargs)
# set_geometry ensures the geometry data have the proper dtype,
# but is not called if `geometry=None` ('geometry' column present
# in the data), so therefore need to ensure it here manually
# but within a try/except because currently non-geometries are
# allowed in that case
# TODO do we want to raise / return normal DataFrame in this case?
# if gdf passed in and geo_col is set, we use that for geometry
if geometry is None and isinstance(data, GeoDataFrame):
self._geometry_column_name = data._geometry_column_name
if crs is not None and data.crs != crs:
raise ValueError(crs_mismatch_error)
if (
geometry is None
and self.columns.nlevels == 1
and "geometry" in self.columns
):
# Check for multiple columns with name "geometry". If there are,
# self["geometry"] is a gdf and constructor gets recursively recalled
# by pandas internals trying to access this
if (self.columns == "geometry").sum() > 1:
raise ValueError(
"GeoDataFrame does not support multiple columns "
"using the geometry column name 'geometry'."
)
# only if we have actual geometry values -> call set_geometry
try:
if (
hasattr(self["geometry"].values, "crs")
and self["geometry"].values.crs
and crs
and not self["geometry"].values.crs == crs
):
raise ValueError(crs_mismatch_error)
self["geometry"] = _ensure_geometry(self["geometry"].values, crs)
except TypeError:
pass
else:
geometry = "geometry"
if geometry is not None:
if (
hasattr(geometry, "crs")
and geometry.crs
and crs
and not geometry.crs == crs
):
raise ValueError(crs_mismatch_error)
if hasattr(geometry, "name") and geometry.name not in ("geometry", None):
# __init__ always creates geometry col named "geometry"
# rename as `set_geometry` respects the given series name
geometry = geometry.rename("geometry")
self.set_geometry(geometry, inplace=True, crs=crs)
if geometry is None and crs:
raise ValueError(
"Assigning CRS to a GeoDataFrame without a geometry column is not "
"supported. Supply geometry using the 'geometry=' keyword argument, "
"or by providing a DataFrame with column name 'geometry'",
)
def __setattr__(self, attr, val):
# have to special case geometry b/c pandas tries to use as column...
if attr == "geometry":
object.__setattr__(self, attr, val)
else:
super().__setattr__(attr, val)
def _get_geometry(self):
if self._geometry_column_name not in self:
if self._geometry_column_name is None:
msg = (
"You are calling a geospatial method on the GeoDataFrame, "
"but the active geometry column to use has not been set. "
)
else:
msg = (
"You are calling a geospatial method on the GeoDataFrame, "
f"but the active geometry column ('{self._geometry_column_name}') "
"is not present. "
)
geo_cols = list(self.columns[self.dtypes == "geometry"])
if len(geo_cols) > 0:
msg += (
f"\nThere are columns with geometry data type ({geo_cols}), and "
"you can either set one as the active geometry with "
'df.set_geometry("name") or access the column as a '
'GeoSeries (df["name"]) and call the method directly on it.'
)
else:
msg += (
"\nThere are no existing columns with geometry data type. You can "
"add a geometry column as the active geometry column with "
"df.set_geometry. "
)
raise AttributeError(msg)
return self[self._geometry_column_name]
def _set_geometry(self, col):
if not pd.api.types.is_list_like(col):
raise ValueError("Must use a list-like to set the geometry property")
self._persist_old_default_geometry_colname()
self.set_geometry(col, inplace=True)
geometry = property(
fget=_get_geometry, fset=_set_geometry, doc="Geometry data for GeoDataFrame"
)
def set_geometry(self, col, drop=None, inplace=False, crs=None):
"""
Set the GeoDataFrame geometry using either an existing column or
the specified input. By default yields a new object.
The original geometry column is replaced with the input.
Parameters
----------
col : column label or array-like
An existing column name or values to set as the new geometry column.
If values (array-like, (Geo)Series) are passed, then if they are named
(Series) the new geometry column will have the corresponding name,
otherwise the existing geometry column will be replaced. If there is
no existing geometry column, the new geometry column will use the
default name "geometry".
drop : boolean, default False
When specifying a named Series or an existing column name for `col`,
controls if the previous geometry column should be dropped from the
result. The default of False keeps both the old and new geometry column.
.. deprecated:: 1.0.0
inplace : boolean, default False
Modify the GeoDataFrame in place (do not create a new object)
crs : pyproj.CRS, optional
Coordinate system to use. The value can be anything accepted
by :meth:`pyproj.CRS.from_user_input() <pyproj.crs.CRS.from_user_input>`,
such as an authority string (eg "EPSG:4326") or a WKT string.
If passed, overrides both DataFrame and col's crs.
Otherwise, tries to get crs from passed col values or DataFrame.
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d, crs="EPSG:4326")
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
Passing an array:
>>> df1 = gdf.set_geometry([Point(0,0), Point(1,1)])
>>> df1
col1 geometry
0 name1 POINT (0 0)
1 name2 POINT (1 1)
Using existing column:
>>> gdf["buffered"] = gdf.buffer(2)
>>> df2 = gdf.set_geometry("buffered")
>>> df2.geometry
0 POLYGON ((3 2, 2.99037 1.80397, 2.96157 1.6098...
1 POLYGON ((4 1, 3.99037 0.80397, 3.96157 0.6098...
Name: buffered, dtype: geometry
Returns
-------
GeoDataFrame
See also
--------
GeoDataFrame.rename_geometry : rename an active geometry column
"""
# Most of the code here is taken from DataFrame.set_index()
if inplace:
frame = self
else:
if PANDAS_GE_30:
frame = self.copy(deep=False)
else:
frame = self.copy()
geo_column_name = self._geometry_column_name
if geo_column_name is None:
geo_column_name = "geometry"
if isinstance(col, (Series, list, np.ndarray, GeometryArray)):
if drop:
msg = (
"The `drop` keyword argument is deprecated and has no effect when "
"`col` is an array-like value. You should stop passing `drop` to "
"`set_geometry` when this is the case."
)
warnings.warn(msg, category=FutureWarning, stacklevel=2)
if isinstance(col, Series) and col.name is not None:
geo_column_name = col.name
level = col
elif hasattr(col, "ndim") and col.ndim > 1:
raise ValueError("Must pass array with one dimension only.")
else: # should be a colname
try:
level = frame[col]
except KeyError:
raise ValueError("Unknown column %s" % col)
if isinstance(level, DataFrame):
raise ValueError(
"GeoDataFrame does not support setting the geometry column where "
"the column name is shared by multiple columns."
)
given_colname_drop_msg = (
"The `drop` keyword argument is deprecated and in future the only "
"supported behaviour will match drop=False. To silence this "
"warning and adopt the future behaviour, stop providing "
"`drop` as a keyword to `set_geometry`. To replicate the "
"`drop=True` behaviour you should update "
"your code to\n`geo_col_name = gdf.active_geometry_name;"
" gdf.set_geometry(new_geo_col).drop("
"columns=geo_col_name).rename_geometry(geo_col_name)`."
)
if drop is False: # specifically False, not falsy i.e. None
# User supplied False explicitly, but arg is deprecated
warnings.warn(
given_colname_drop_msg,
category=FutureWarning,
stacklevel=2,
)
if drop:
del frame[col]
warnings.warn(
given_colname_drop_msg,
category=FutureWarning,
stacklevel=2,
)
else:
# if not dropping, set the active geometry name to the given col name
geo_column_name = col
if not crs:
crs = getattr(level, "crs", None)
# Check that we are using a listlike of geometries
level = _ensure_geometry(level, crs=crs)
# ensure_geometry only sets crs on level if it has crs==None
if isinstance(level, GeoSeries):
level.array.crs = crs
else:
level.crs = crs
# update _geometry_column_name prior to assignment
# to avoid default is None warning
frame._geometry_column_name = geo_column_name
frame[geo_column_name] = level
if not inplace:
return frame
def rename_geometry(self, col, inplace=False):
"""
Renames the GeoDataFrame geometry column to
the specified name. By default yields a new object.
The original geometry column is replaced with the input.
Parameters
----------
col : new geometry column label
inplace : boolean, default False
Modify the GeoDataFrame in place (do not create a new object)
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> df = geopandas.GeoDataFrame(d, crs="EPSG:4326")
>>> df1 = df.rename_geometry('geom1')
>>> df1.geometry.name
'geom1'
>>> df.rename_geometry('geom1', inplace=True)
>>> df.geometry.name
'geom1'
Returns
-------
geodataframe : GeoDataFrame
See also
--------
GeoDataFrame.set_geometry : set the active geometry
"""
geometry_col = self.geometry.name
if col in self.columns:
raise ValueError(f"Column named {col} already exists")
else:
if not inplace:
return self.rename(columns={geometry_col: col}).set_geometry(
col, inplace=inplace
)
self.rename(columns={geometry_col: col}, inplace=inplace)
self.set_geometry(col, inplace=inplace)
@property
def active_geometry_name(self):
"""Return the name of the active geometry column
Returns a string name if a GeoDataFrame has an active geometry column set.
Otherwise returns None. You can also access the active geometry column using the
``.geometry`` property. You can set a GeoSeries to be an active geometry
using the :meth:`~GeoDataFrame.set_geometry` method.
Returns
-------
str
name of an active geometry column or None
See also
--------
GeoDataFrame.set_geometry : set the active geometry
"""
return self._geometry_column_name
@property
def crs(self):
"""
The Coordinate Reference System (CRS) represented as a ``pyproj.CRS``
object.
Returns None if the CRS is not set, and to set the value it
:getter: Returns a ``pyproj.CRS`` or None. When setting, the value
can be anything accepted by
:meth:`pyproj.CRS.from_user_input() <pyproj.crs.CRS.from_user_input>`,
such as an authority string (eg "EPSG:4326") or a WKT string.
Examples
--------
>>> gdf.crs # doctest: +SKIP
<Geographic 2D CRS: EPSG:4326>
Name: WGS 84
Axis Info [ellipsoidal]:
- Lat[north]: Geodetic latitude (degree)
- Lon[east]: Geodetic longitude (degree)
Area of Use:
- name: World
- bounds: (-180.0, -90.0, 180.0, 90.0)
Datum: World Geodetic System 1984
- Ellipsoid: WGS 84
- Prime Meridian: Greenwich
See also
--------
GeoDataFrame.set_crs : assign CRS
GeoDataFrame.to_crs : re-project to another CRS
"""
try:
return self.geometry.crs
except AttributeError:
raise AttributeError(
"The CRS attribute of a GeoDataFrame without an active "
"geometry column is not defined. Use GeoDataFrame.set_geometry "
"to set the active geometry column."
)
@crs.setter
def crs(self, value):
"""Sets the value of the crs"""
if self._geometry_column_name is None:
raise ValueError(
"Assigning CRS to a GeoDataFrame without a geometry column is not "
"supported. Use GeoDataFrame.set_geometry to set the active "
"geometry column.",
)
if hasattr(self.geometry.values, "crs"):
if self.crs is not None:
warnings.warn(
"Overriding the CRS of a GeoDataFrame that already has CRS. "
"This unsafe behavior will be deprecated in future versions. "
"Use GeoDataFrame.set_crs method instead",
stacklevel=2,
category=DeprecationWarning,
)
self.geometry.values.crs = value
else:
# column called 'geometry' without geometry
raise ValueError(
"Assigning CRS to a GeoDataFrame without an active geometry "
"column is not supported. Use GeoDataFrame.set_geometry to set "
"the active geometry column.",
)
def __setstate__(self, state):
# overriding DataFrame method for compat with older pickles (CRS handling)
crs = None
if isinstance(state, dict):
if "crs" in state and "_crs" not in state:
crs = state.pop("crs", None)
else:
crs = state.pop("_crs", None)
if crs is not None and not HAS_PYPROJ:
raise ImportError(
"Unpickling a GeoDataFrame with CRS requires the 'pyproj' package, "
"but it is not installed or does not import correctly. "
)
elif crs is not None:
from pyproj import CRS
crs = CRS.from_user_input(crs)
super().__setstate__(state)
# for some versions that didn't yet have CRS at array level -> crs is set
# at GeoDataFrame level with '_crs' (and not 'crs'), so without propagating
# to the GeoSeries/GeometryArray
try:
if crs is not None:
if self.geometry.values.crs is None:
self.crs = crs
except Exception:
pass
@classmethod
def from_dict(cls, data, geometry=None, crs=None, **kwargs):
"""
Construct GeoDataFrame from dict of array-like or dicts by
overriding DataFrame.from_dict method with geometry and crs
Parameters
----------
data : dict
Of the form {field : array-like} or {field : dict}.
geometry : str or array (optional)
If str, column to use as geometry. If array, will be set as 'geometry'
column on GeoDataFrame.
crs : str or dict (optional)
Coordinate reference system to set on the resulting frame.
kwargs : key-word arguments
These arguments are passed to DataFrame.from_dict
Returns
-------
GeoDataFrame
"""
dataframe = DataFrame.from_dict(data, **kwargs)
return cls(dataframe, geometry=geometry, crs=crs)
@classmethod
def from_file(cls, filename, **kwargs):
"""Alternate constructor to create a ``GeoDataFrame`` from a file.
It is recommended to use :func:`geopandas.read_file` instead.
Can load a ``GeoDataFrame`` from a file in any format recognized by
`pyogrio`. See http://pyogrio.readthedocs.io/ for details.
Parameters
----------
filename : str
File path or file handle to read from. Depending on which kwargs
are included, the content of filename may vary. See
:func:`pyogrio.read_dataframe` for usage details.
kwargs : key-word arguments
These arguments are passed to :func:`pyogrio.read_dataframe`, and can be
used to access multi-layer data, data stored within archives (zip files),
etc.
Examples
--------
>>> import geodatasets
>>> path = geodatasets.get_path('nybb')
>>> gdf = geopandas.GeoDataFrame.from_file(path)
>>> gdf # doctest: +SKIP
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...
The recommended method of reading files is :func:`geopandas.read_file`:
>>> gdf = geopandas.read_file(path)
See also
--------
read_file : read file to GeoDataFame
GeoDataFrame.to_file : write GeoDataFrame to file
"""
return geopandas.io.file._read_file(filename, **kwargs)
@classmethod
def from_features(cls, features, crs=None, columns=None):
"""
Alternate constructor to create GeoDataFrame from an iterable of
features or a feature collection.
Parameters
----------
features
- Iterable of features, where each element must be a feature
dictionary or implement the __geo_interface__.
- Feature collection, where the 'features' key contains an
iterable of features.
- Object holding a feature collection that implements the
``__geo_interface__``.
crs : str or dict (optional)
Coordinate reference system to set on the resulting frame.
columns : list of column names, optional
Optionally specify the column names to include in the output frame.
This does not overwrite the property names of the input, but can
ensure a consistent output format.
Returns
-------
GeoDataFrame
Notes
-----
For more information about the ``__geo_interface__``, see
https://gist.github.com/sgillies/2217756
Examples
--------
>>> feature_coll = {
... "type": "FeatureCollection",
... "features": [
... {
... "id": "0",
... "type": "Feature",
... "properties": {"col1": "name1"},
... "geometry": {"type": "Point", "coordinates": (1.0, 2.0)},
... "bbox": (1.0, 2.0, 1.0, 2.0),
... },
... {
... "id": "1",
... "type": "Feature",
... "properties": {"col1": "name2"},
... "geometry": {"type": "Point", "coordinates": (2.0, 1.0)},
... "bbox": (2.0, 1.0, 2.0, 1.0),
... },
... ],
... "bbox": (1.0, 1.0, 2.0, 2.0),
... }
>>> df = geopandas.GeoDataFrame.from_features(feature_coll)
>>> df
geometry col1
0 POINT (1 2) name1
1 POINT (2 1) name2
"""
# Handle feature collections
if hasattr(features, "__geo_interface__"):
fs = features.__geo_interface__
else:
fs = features
if isinstance(fs, dict) and fs.get("type") == "FeatureCollection":
features_lst = fs["features"]
else:
features_lst = features
rows = []
for feature in features_lst:
# load geometry
if hasattr(feature, "__geo_interface__"):
feature = feature.__geo_interface__
row = {
"geometry": shape(feature["geometry"]) if feature["geometry"] else None
}
# load properties
properties = feature["properties"]
if properties is None:
properties = {}
row.update(properties)
rows.append(row)
return cls(rows, columns=columns, crs=crs)
@classmethod
def from_postgis(
cls,
sql,
con,
geom_col="geom",
crs=None,
index_col=None,
coerce_float=True,
parse_dates=None,
params=None,
chunksize=None,
):
"""
Alternate constructor to create a ``GeoDataFrame`` from a sql query
containing a geometry column in WKB representation.
Parameters
----------
sql : string
con : sqlalchemy.engine.Connection or sqlalchemy.engine.Engine
geom_col : string, default 'geom'
column name to convert to shapely geometries
crs : optional
Coordinate reference system to use for the returned GeoDataFrame
index_col : string or list of strings, optional, default: None
Column(s) to set as index(MultiIndex)
coerce_float : boolean, default True
Attempt to convert values of non-string, non-numeric objects (like
decimal.Decimal) to floating point, useful for SQL result sets
parse_dates : list or dict, default None
- List of column names to parse as dates.
- Dict of ``{column_name: format string}`` where format string is
strftime compatible in case of parsing string times, or is one of
(D, s, ns, ms, us) in case of parsing integer timestamps.
- Dict of ``{column_name: arg dict}``, where the arg dict
corresponds to the keyword arguments of
:func:`pandas.to_datetime`. Especially useful with databases
without native Datetime support, such as SQLite.
params : list, tuple or dict, optional, default None
List of parameters to pass to execute method.
chunksize : int, default None
If specified, return an iterator where chunksize is the number
of rows to include in each chunk.
Examples
--------
PostGIS
>>> from sqlalchemy import create_engine # doctest: +SKIP
>>> db_connection_url = "postgresql://myusername:mypassword@myhost:5432/mydb"
>>> con = create_engine(db_connection_url) # doctest: +SKIP
>>> sql = "SELECT geom, highway FROM roads"
>>> df = geopandas.GeoDataFrame.from_postgis(sql, con) # doctest: +SKIP
SpatiaLite
>>> sql = "SELECT ST_Binary(geom) AS geom, highway FROM roads"
>>> df = geopandas.GeoDataFrame.from_postgis(sql, con) # doctest: +SKIP
The recommended method of reading from PostGIS is
:func:`geopandas.read_postgis`:
>>> df = geopandas.read_postgis(sql, con) # doctest: +SKIP
See also
--------
geopandas.read_postgis : read PostGIS database to GeoDataFrame
"""
df = geopandas.io.sql._read_postgis(
sql,
con,
geom_col=geom_col,
crs=crs,
index_col=index_col,
coerce_float=coerce_float,
parse_dates=parse_dates,
params=params,
chunksize=chunksize,
)
return df
@classmethod
def from_arrow(cls, table, geometry=None):
"""
Construct a GeoDataFrame from a Arrow table object based on GeoArrow
extension types.
See https://geoarrow.org/ for details on the GeoArrow specification.
This functions accepts any tabular Arrow object implementing
the `Arrow PyCapsule Protocol`_ (i.e. having an ``__arrow_c_array__``
or ``__arrow_c_stream__`` method).
.. _Arrow PyCapsule Protocol: https://arrow.apache.org/docs/format/CDataInterface/PyCapsuleInterface.html
.. versionadded:: 1.0
Parameters
----------
table : pyarrow.Table or Arrow-compatible table
Any tabular object implementing the Arrow PyCapsule Protocol
(i.e. has an ``__arrow_c_array__`` or ``__arrow_c_stream__``
method). This table should have at least one column with a
geoarrow geometry type.
geometry : str, default None
The name of the geometry column to set as the active geometry
column. If None, the first geometry column found will be used.
Returns
-------
GeoDataFrame
"""
from geopandas.io._geoarrow import arrow_to_geopandas
return arrow_to_geopandas(table, geometry=geometry)
def to_json(
self, na="null", show_bbox=False, drop_id=False, to_wgs84=False, **kwargs
):
"""
Returns a GeoJSON representation of the ``GeoDataFrame`` as a string.
Parameters
----------
na : {'null', 'drop', 'keep'}, default 'null'
Indicates how to output missing (NaN) values in the GeoDataFrame.
See below.
show_bbox : bool, optional, default: False
Include bbox (bounds) in the geojson
drop_id : bool, default: False
Whether to retain the index of the GeoDataFrame as the id property
in the generated GeoJSON. Default is False, but may want True
if the index is just arbitrary row numbers.
to_wgs84: bool, optional, default: False
If the CRS is set on the active geometry column it is exported as
WGS84 (EPSG:4326) to meet the `2016 GeoJSON specification
<https://tools.ietf.org/html/rfc7946>`_.
Set to True to force re-projection and set to False to ignore CRS. False by
default.
Notes
-----
The remaining *kwargs* are passed to json.dumps().
Missing (NaN) values in the GeoDataFrame can be represented as follows:
- ``null``: output the missing entries as JSON null.
- ``drop``: remove the property from the feature. This applies to each
feature individually so that features may have different properties.
- ``keep``: output the missing entries as NaN.
If the GeoDataFrame has a defined CRS, its definition will be included
in the output unless it is equal to WGS84 (default GeoJSON CRS) or not
possible to represent in the URN OGC format, or unless ``to_wgs84=True``
is specified.
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d, crs="EPSG:3857")
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
>>> gdf.to_json()
'{"type": "FeatureCollection", "features": [{"id": "0", "type": "Feature", \
"properties": {"col1": "name1"}, "geometry": {"type": "Point", "coordinates": [1.0,\
2.0]}}, {"id": "1", "type": "Feature", "properties": {"col1": "name2"}, "geometry"\
: {"type": "Point", "coordinates": [2.0, 1.0]}}], "crs": {"type": "name", "properti\
es": {"name": "urn:ogc:def:crs:EPSG::3857"}}}'
Alternatively, you can write GeoJSON to file:
>>> gdf.to_file(path, driver="GeoJSON") # doctest: +SKIP
See also
--------
GeoDataFrame.to_file : write GeoDataFrame to file
"""
if to_wgs84:
if self.crs:
df = self.to_crs(epsg=4326)
else:
raise ValueError(
"CRS is not set. Cannot re-project to WGS84 (EPSG:4326)."
)
else:
df = self
geo = df.to_geo_dict(na=na, show_bbox=show_bbox, drop_id=drop_id)
# if the geometry is not in WGS84, include CRS in the JSON
if df.crs is not None and not df.crs.equals("epsg:4326"):
auth_crsdef = self.crs.to_authority()
allowed_authorities = ["EDCS", "EPSG", "OGC", "SI", "UCUM"]
if auth_crsdef is None or auth_crsdef[0] not in allowed_authorities:
warnings.warn(
"GeoDataFrame's CRS is not representable in URN OGC "
"format. Resulting JSON will contain no CRS information.",
stacklevel=2,
)
else:
authority, code = auth_crsdef
ogc_crs = f"urn:ogc:def:crs:{authority}::{code}"
geo["crs"] = {"type": "name", "properties": {"name": ogc_crs}}
return json.dumps(geo, **kwargs)
@property
def __geo_interface__(self):
"""Returns a ``GeoDataFrame`` as a python feature collection.
Implements the `geo_interface`. The returned python data structure
represents the ``GeoDataFrame`` as a GeoJSON-like
``FeatureCollection``.
This differs from :meth:`to_geo_dict` only in that it is a property with
default args instead of a method.
CRS of the dataframe is not passed on to the output, unlike
:meth:`~GeoDataFrame.to_json()`.
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d, crs="EPSG:4326")
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
>>> gdf.__geo_interface__
{'type': 'FeatureCollection', 'features': [{'id': '0', 'type': 'Feature', \
'properties': {'col1': 'name1'}, 'geometry': {'type': 'Point', 'coordinates': (1.0\
, 2.0)}, 'bbox': (1.0, 2.0, 1.0, 2.0)}, {'id': '1', 'type': 'Feature', 'properties\
': {'col1': 'name2'}, 'geometry': {'type': 'Point', 'coordinates': (2.0, 1.0)}, 'b\
box': (2.0, 1.0, 2.0, 1.0)}], 'bbox': (1.0, 1.0, 2.0, 2.0)}
"""
return self.to_geo_dict(na="null", show_bbox=True, drop_id=False)
def iterfeatures(self, na="null", show_bbox=False, drop_id=False):
"""
Returns an iterator that yields feature dictionaries that comply with
__geo_interface__
Parameters
----------
na : str, optional
Options are {'null', 'drop', 'keep'}, default 'null'.
Indicates how to output missing (NaN) values in the GeoDataFrame
- null: output the missing entries as JSON null
- drop: remove the property from the feature. This applies to each feature \
individually so that features may have different properties
- keep: output the missing entries as NaN
show_bbox : bool, optional
Include bbox (bounds) in the geojson. Default False.
drop_id : bool, default: False
Whether to retain the index of the GeoDataFrame as the id property
in the generated GeoJSON. Default is False, but may want True
if the index is just arbitrary row numbers.
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d, crs="EPSG:4326")
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
>>> feature = next(gdf.iterfeatures())
>>> feature
{'id': '0', 'type': 'Feature', 'properties': {'col1': 'name1'}, 'geometry': {\
'type': 'Point', 'coordinates': (1.0, 2.0)}}
"""
if na not in ["null", "drop", "keep"]:
raise ValueError("Unknown na method {0}".format(na))
if self._geometry_column_name not in self:
raise AttributeError(
"No geometry data set (expected in column '%s')."
% self._geometry_column_name
)
ids = np.array(self.index, copy=False)
geometries = np.array(self[self._geometry_column_name], copy=False)
if not self.columns.is_unique:
raise ValueError("GeoDataFrame cannot contain duplicated column names.")
properties_cols = self.columns.drop(self._geometry_column_name)
if len(properties_cols) > 0:
# convert to object to get python scalars.
properties_cols = self[properties_cols]
properties = properties_cols.astype(object)
na_mask = pd.isna(properties_cols).values
if na == "null":
properties[na_mask] = None
for i, row in enumerate(properties.values):
geom = geometries[i]
if na == "drop":
na_mask_row = na_mask[i]
properties_items = {
k: v
for k, v, na in zip(properties_cols, row, na_mask_row)
if not na
}
else:
properties_items = dict(zip(properties_cols, row))
if drop_id:
feature = {}
else:
feature = {"id": str(ids[i])}
feature["type"] = "Feature"
feature["properties"] = properties_items
feature["geometry"] = mapping(geom) if geom else None
if show_bbox:
feature["bbox"] = geom.bounds if geom else None
yield feature
else:
for fid, geom in zip(ids, geometries):
if drop_id:
feature = {}
else:
feature = {"id": str(fid)}
feature["type"] = "Feature"
feature["properties"] = {}
feature["geometry"] = mapping(geom) if geom else None
if show_bbox:
feature["bbox"] = geom.bounds if geom else None
yield feature
def to_geo_dict(self, na="null", show_bbox=False, drop_id=False):
"""
Returns a python feature collection representation of the GeoDataFrame
as a dictionary with a list of features based on the ``__geo_interface__``
GeoJSON-like specification.
Parameters
----------
na : str, optional
Options are {'null', 'drop', 'keep'}, default 'null'.
Indicates how to output missing (NaN) values in the GeoDataFrame
- null: output the missing entries as JSON null
- drop: remove the property from the feature. This applies to each feature \
individually so that features may have different properties
- keep: output the missing entries as NaN
show_bbox : bool, optional
Include bbox (bounds) in the geojson. Default False.
drop_id : bool, default: False
Whether to retain the index of the GeoDataFrame as the id property
in the generated dictionary. Default is False, but may want True
if the index is just arbitrary row numbers.
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d)
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
>>> gdf.to_geo_dict()
{'type': 'FeatureCollection', 'features': [{'id': '0', 'type': 'Feature', '\
properties': {'col1': 'name1'}, 'geometry': {'type': 'Point', 'coordinates': (1.0, \
2.0)}}, {'id': '1', 'type': 'Feature', 'properties': {'col1': 'name2'}, 'geometry':\
{'type': 'Point', 'coordinates': (2.0, 1.0)}}]}
See also
--------
GeoDataFrame.to_json : return a GeoDataFrame as a GeoJSON string
"""
geo = {
"type": "FeatureCollection",
"features": list(
self.iterfeatures(na=na, show_bbox=show_bbox, drop_id=drop_id)
),
}
if show_bbox:
geo["bbox"] = tuple(self.total_bounds)
return geo
def to_wkb(self, hex=False, **kwargs):
"""
Encode all geometry columns in the GeoDataFrame to WKB.
Parameters
----------
hex : bool
If true, export the WKB as a hexadecimal string.
The default is to return a binary bytes object.
kwargs
Additional keyword args will be passed to
:func:`shapely.to_wkb`.
Returns
-------
DataFrame
geometry columns are encoded to WKB
"""
df = DataFrame(self.copy())
# Encode all geometry columns to WKB
for col in df.columns[df.dtypes == "geometry"]:
df[col] = to_wkb(df[col].values, hex=hex, **kwargs)
return df
def to_wkt(self, **kwargs):
"""
Encode all geometry columns in the GeoDataFrame to WKT.
Parameters
----------
kwargs
Keyword args will be passed to :func:`shapely.to_wkt`.
Returns
-------
DataFrame
geometry columns are encoded to WKT
"""
df = DataFrame(self.copy())
# Encode all geometry columns to WKT
for col in df.columns[df.dtypes == "geometry"]:
df[col] = to_wkt(df[col].values, **kwargs)
return df
def to_arrow(
self, *, index=None, geometry_encoding="WKB", interleaved=True, include_z=None
):
"""Encode a GeoDataFrame to GeoArrow format.
See https://geoarrow.org/ for details on the GeoArrow specification.
This functions returns a generic Arrow data object implementing
the `Arrow PyCapsule Protocol`_ (i.e. having an ``__arrow_c_stream__``
method). This object can then be consumed by your Arrow implementation
of choice that supports this protocol.
.. _Arrow PyCapsule Protocol: https://arrow.apache.org/docs/format/CDataInterface/PyCapsuleInterface.html
.. versionadded:: 1.0
Parameters
----------
index : bool, default None
If ``True``, always include the dataframe's index(es) as columns
in the file output.
If ``False``, the index(es) will not be written to the file.
If ``None``, the index(ex) will be included as columns in the file
output except `RangeIndex` which is stored as metadata only.
geometry_encoding : {'WKB', 'geoarrow' }, default 'WKB'
The GeoArrow encoding to use for the data conversion.
interleaved : bool, default True
Only relevant for 'geoarrow' encoding. If True, the geometries'
coordinates are interleaved in a single fixed size list array.
If False, the coordinates are stored as separate arrays in a
struct type.
include_z : bool, default None
Only relevant for 'geoarrow' encoding (for WKB, the dimensionality
of the individial geometries is preserved).
If False, return 2D geometries. If True, include the third dimension
in the output (if a geometry has no third dimension, the z-coordinates
will be NaN). By default, will infer the dimensionality from the
input geometries. Note that this inference can be unreliable with
empty geometries (for a guaranteed result, it is recommended to
specify the keyword).
Returns
-------
ArrowTable
A generic Arrow table object with geometry columns encoded to
GeoArrow.
Examples
--------
>>> from shapely.geometry import Point
>>> data = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(data)
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
>>> arrow_table = gdf.to_arrow()
>>> arrow_table
<geopandas.io._geoarrow.ArrowTable object at ...>
The returned data object needs to be consumed by a library implementing
the Arrow PyCapsule Protocol. For example, wrapping the data as a
pyarrow.Table (requires pyarrow >= 14.0):
>>> import pyarrow as pa
>>> table = pa.table(arrow_table)
>>> table
pyarrow.Table
col1: string
geometry: binary
----
col1: [["name1","name2"]]
geometry: [[0101000000000000000000F03F0000000000000040,\
01010000000000000000000040000000000000F03F]]
"""
from geopandas.io._geoarrow import ArrowTable, geopandas_to_arrow
table, _ = geopandas_to_arrow(
self,
index=index,
geometry_encoding=geometry_encoding,
interleaved=interleaved,
include_z=include_z,
)
return ArrowTable(table)
def to_parquet(
self,
path,
index=None,
compression="snappy",
geometry_encoding="WKB",
write_covering_bbox=False,
schema_version=None,
**kwargs,
):
"""Write a GeoDataFrame to the Parquet format.
By default, all geometry columns present are serialized to WKB format
in the file.
Requires 'pyarrow'.
.. versionadded:: 0.8
Parameters
----------
path : str, path object
index : bool, default None
If ``True``, always include the dataframe's index(es) as columns
in the file output.
If ``False``, the index(es) will not be written to the file.
If ``None``, the index(ex) will be included as columns in the file
output except `RangeIndex` which is stored as metadata only.
compression : {'snappy', 'gzip', 'brotli', None}, default 'snappy'
Name of the compression to use. Use ``None`` for no compression.
geometry_encoding : {'WKB', 'geoarrow'}, default 'WKB'
The encoding to use for the geometry columns. Defaults to "WKB"
for maximum interoperability. Specify "geoarrow" to use one of the
native GeoArrow-based single-geometry type encodings.
Note: the "geoarrow" option is part of the newer GeoParquet 1.1
specification, should be considered as experimental, and may not
be supported by all readers.
write_covering_bbox : bool, default False
Writes the bounding box column for each row entry with column
name 'bbox'. Writing a bbox column can be computationally
expensive, but allows you to specify a `bbox` in :
func:`read_parquet` for filtered reading.
Note: this bbox column is part of the newer GeoParquet 1.1
specification and should be considered as experimental. While
writing the column is backwards compatible, using it for filtering
may not be supported by all readers.
schema_version : {'0.1.0', '0.4.0', '1.0.0', '1.1.0', None}
GeoParquet specification version; if not provided, will default to
latest supported stable version (1.0.0).
kwargs
Additional keyword arguments passed to :func:`pyarrow.parquet.write_table`.
Examples
--------
>>> gdf.to_parquet('data.parquet') # doctest: +SKIP
See also
--------
GeoDataFrame.to_feather : write GeoDataFrame to feather
GeoDataFrame.to_file : write GeoDataFrame to file
"""
# Accept engine keyword for compatibility with pandas.DataFrame.to_parquet
# The only engine currently supported by GeoPandas is pyarrow, so no
# other engine should be specified.
engine = kwargs.pop("engine", "auto")
if engine not in ("auto", "pyarrow"):
raise ValueError(
"GeoPandas only supports using pyarrow as the engine for "
f"to_parquet: {engine!r} passed instead."
)
from geopandas.io.arrow import _to_parquet
_to_parquet(
self,
path,
compression=compression,
geometry_encoding=geometry_encoding,
index=index,
schema_version=schema_version,
write_covering_bbox=write_covering_bbox,
**kwargs,
)
def to_feather(
self, path, index=None, compression=None, schema_version=None, **kwargs
):
"""Write a GeoDataFrame to the Feather format.
Any geometry columns present are serialized to WKB format in the file.
Requires 'pyarrow' >= 0.17.
.. versionadded:: 0.8
Parameters
----------
path : str, path object
index : bool, default None
If ``True``, always include the dataframe's index(es) as columns
in the file output.
If ``False``, the index(es) will not be written to the file.
If ``None``, the index(ex) will be included as columns in the file
output except `RangeIndex` which is stored as metadata only.
compression : {'zstd', 'lz4', 'uncompressed'}, optional
Name of the compression to use. Use ``"uncompressed"`` for no
compression. By default uses LZ4 if available, otherwise uncompressed.
schema_version : {'0.1.0', '0.4.0', '1.0.0', None}
GeoParquet specification version; if not provided will default to
latest supported version.
kwargs
Additional keyword arguments passed to to
:func:`pyarrow.feather.write_feather`.
Examples
--------
>>> gdf.to_feather('data.feather') # doctest: +SKIP
See also
--------
GeoDataFrame.to_parquet : write GeoDataFrame to parquet
GeoDataFrame.to_file : write GeoDataFrame to file
"""
from geopandas.io.arrow import _to_feather
_to_feather(
self,
path,
index=index,
compression=compression,
schema_version=schema_version,
**kwargs,
)
def to_file(self, filename, driver=None, schema=None, index=None, **kwargs):
"""Write the ``GeoDataFrame`` to a file.
By default, an ESRI shapefile is written, but any OGR data source
supported by Pyogrio or Fiona can be written. A dictionary of supported OGR
providers is available via:
>>> import pyogrio
>>> pyogrio.list_drivers() # doctest: +SKIP
Parameters
----------
filename : string
File path or file handle to write to. The path may specify a
GDAL VSI scheme.
driver : string, default None
The OGR format driver used to write the vector file.
If not specified, it attempts to infer it from the file extension.
If no extension is specified, it saves ESRI Shapefile to a folder.
schema : dict, default None
If specified, the schema dictionary is passed to Fiona to
better control how the file is written. If None, GeoPandas
will determine the schema based on each column's dtype.
Not supported for the "pyogrio" engine.
index : bool, default None
If True, write index into one or more columns (for MultiIndex).
Default None writes the index into one or more columns only if
the index is named, is a MultiIndex, or has a non-integer data
type. If False, no index is written.
.. versionadded:: 0.7
Previously the index was not written.
mode : string, default 'w'
The write mode, 'w' to overwrite the existing file and 'a' to append.
Not all drivers support appending. The drivers that support appending
are listed in fiona.supported_drivers or
https://github.com/Toblerity/Fiona/blob/master/fiona/drvsupport.py
crs : pyproj.CRS, default None
If specified, the CRS is passed to Fiona to
better control how the file is written. If None, GeoPandas
will determine the crs based on crs df attribute.
The value can be anything accepted
by :meth:`pyproj.CRS.from_user_input() <pyproj.crs.CRS.from_user_input>`,
such as an authority string (eg "EPSG:4326") or a WKT string. The keyword
is not supported for the "pyogrio" engine.
engine : str, "pyogrio" or "fiona"
The underlying library that is used to write the file. Currently, the
supported options are "pyogrio" and "fiona". Defaults to "pyogrio" if
installed, otherwise tries "fiona".
metadata : dict[str, str], default None
Optional metadata to be stored in the file. Keys and values must be
strings. Supported only for "GPKG" driver.
**kwargs :
Keyword args to be passed to the engine, and can be used to write
to multi-layer data, store data within archives (zip files), etc.
In case of the "pyogrio" engine, the keyword arguments are passed to
`pyogrio.write_dataframe`. In case of the "fiona" engine, the keyword
arguments are passed to fiona.open`. For more information on possible
keywords, type: ``import pyogrio; help(pyogrio.write_dataframe)``.
Notes
-----
The format drivers will attempt to detect the encoding of your data, but
may fail. In this case, the proper encoding can be specified explicitly
by using the encoding keyword parameter, e.g. ``encoding='utf-8'``.
See Also
--------
GeoSeries.to_file
GeoDataFrame.to_postgis : write GeoDataFrame to PostGIS database
GeoDataFrame.to_parquet : write GeoDataFrame to parquet
GeoDataFrame.to_feather : write GeoDataFrame to feather
Examples
--------
>>> gdf.to_file('dataframe.shp') # doctest: +SKIP
>>> gdf.to_file('dataframe.gpkg', driver='GPKG', layer='name') # doctest: +SKIP
>>> gdf.to_file('dataframe.geojson', driver='GeoJSON') # doctest: +SKIP
With selected drivers you can also append to a file with `mode="a"`:
>>> gdf.to_file('dataframe.shp', mode="a") # doctest: +SKIP
Using the engine-specific keyword arguments it is possible to e.g. create a
spatialite file with a custom layer name:
>>> gdf.to_file(
... 'dataframe.sqlite', driver='SQLite', spatialite=True, layer='test'
... ) # doctest: +SKIP
"""
from geopandas.io.file import _to_file
_to_file(self, filename, driver, schema, index, **kwargs)
def set_crs(self, crs=None, epsg=None, inplace=False, allow_override=False):
"""
Set the Coordinate Reference System (CRS) of the ``GeoDataFrame``.
If there are multiple geometry columns within the GeoDataFrame, only
the CRS of the active geometry column is set.
Pass ``None`` to remove CRS from the active geometry column.
Notes
-----
The underlying geometries are not transformed to this CRS. To
transform the geometries to a new CRS, use the ``to_crs`` method.
Parameters
----------
crs : pyproj.CRS | None, optional
The value can be anything accepted
by :meth:`pyproj.CRS.from_user_input() <pyproj.crs.CRS.from_user_input>`,
such as an authority string (eg "EPSG:4326") or a WKT string.
epsg : int, optional
EPSG code specifying the projection.
inplace : bool, default False
If True, the CRS of the GeoDataFrame will be changed in place
(while still returning the result) instead of making a copy of
the GeoDataFrame.
allow_override : bool, default False
If the the GeoDataFrame already has a CRS, allow to replace the
existing CRS, even when both are not equal.
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d)
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
Setting CRS to a GeoDataFrame without one:
>>> gdf.crs is None
True
>>> gdf = gdf.set_crs('epsg:3857')
>>> gdf.crs # doctest: +SKIP
<Projected CRS: EPSG:3857>
Name: WGS 84 / Pseudo-Mercator
Axis Info [cartesian]:
- X[east]: Easting (metre)
- Y[north]: Northing (metre)
Area of Use:
- name: World - 85°S to 85°N
- bounds: (-180.0, -85.06, 180.0, 85.06)
Coordinate Operation:
- name: Popular Visualisation Pseudo-Mercator
- method: Popular Visualisation Pseudo Mercator
Datum: World Geodetic System 1984
- Ellipsoid: WGS 84
- Prime Meridian: Greenwich
Overriding existing CRS:
>>> gdf = gdf.set_crs(4326, allow_override=True)
Without ``allow_override=True``, ``set_crs`` returns an error if you try to
override CRS.
See also
--------
GeoDataFrame.to_crs : re-project to another CRS
"""
if not inplace:
df = self.copy()
else:
df = self
df.geometry = df.geometry.set_crs(
crs=crs, epsg=epsg, allow_override=allow_override, inplace=True
)
return df
def to_crs(self, crs=None, epsg=None, inplace=False):
"""Transform geometries to a new coordinate reference system.
Transform all geometries in an active geometry column to a different coordinate
reference system. The ``crs`` attribute on the current GeoSeries must
be set. Either ``crs`` or ``epsg`` may be specified for output.
This method will transform all points in all objects. It has no notion
of projecting entire geometries. All segments joining points are
assumed to be lines in the current projection, not geodesics. Objects
crossing the dateline (or other projection boundary) will have
undesirable behavior.
Parameters
----------
crs : pyproj.CRS, optional if `epsg` is specified
The value can be anything accepted by
:meth:`pyproj.CRS.from_user_input() <pyproj.crs.CRS.from_user_input>`,
such as an authority string (eg "EPSG:4326") or a WKT string.
epsg : int, optional if `crs` is specified
EPSG code specifying output projection.
inplace : bool, optional, default: False
Whether to return a new GeoDataFrame or do the transformation in
place.
Returns
-------
GeoDataFrame
Examples
--------
>>> from shapely.geometry import Point
>>> d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
>>> gdf = geopandas.GeoDataFrame(d, crs=4326)
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
>>> gdf.crs # doctest: +SKIP
<Geographic 2D CRS: EPSG:4326>
Name: WGS 84
Axis Info [ellipsoidal]:
- Lat[north]: Geodetic latitude (degree)
- Lon[east]: Geodetic longitude (degree)
Area of Use:
- name: World
- bounds: (-180.0, -90.0, 180.0, 90.0)
Datum: World Geodetic System 1984
- Ellipsoid: WGS 84
- Prime Meridian: Greenwich
>>> gdf = gdf.to_crs(3857)
>>> gdf
col1 geometry
0 name1 POINT (111319.491 222684.209)
1 name2 POINT (222638.982 111325.143)
>>> gdf.crs # doctest: +SKIP
<Projected CRS: EPSG:3857>
Name: WGS 84 / Pseudo-Mercator
Axis Info [cartesian]:
- X[east]: Easting (metre)
- Y[north]: Northing (metre)
Area of Use:
- name: World - 85°S to 85°N
- bounds: (-180.0, -85.06, 180.0, 85.06)
Coordinate Operation:
- name: Popular Visualisation Pseudo-Mercator
- method: Popular Visualisation Pseudo Mercator
Datum: World Geodetic System 1984
- Ellipsoid: WGS 84
- Prime Meridian: Greenwich
See also
--------
GeoDataFrame.set_crs : assign CRS without re-projection
"""
if inplace:
df = self
else:
df = self.copy()
geom = df.geometry.to_crs(crs=crs, epsg=epsg)
df.geometry = geom
if not inplace:
return df
def estimate_utm_crs(self, datum_name="WGS 84"):
"""Returns the estimated UTM CRS based on the bounds of the dataset.
.. versionadded:: 0.9
Parameters
----------
datum_name : str, optional
The name of the datum to use in the query. Default is WGS 84.
Returns
-------
pyproj.CRS
Examples
--------
>>> import geodatasets
>>> df = geopandas.read_file(
... geodatasets.get_path("geoda.chicago_health")
... )
>>> df.estimate_utm_crs() # doctest: +SKIP
<Derived Projected CRS: EPSG:32616>
Name: WGS 84 / UTM zone 16N
Axis Info [cartesian]:
- E[east]: Easting (metre)
- N[north]: Northing (metre)
Area of Use:
- name: Between 90°W and 84°W, northern hemisphere between equator and 84°N...
- bounds: (-90.0, 0.0, -84.0, 84.0)
Coordinate Operation:
- name: UTM zone 16N
- method: Transverse Mercator
Datum: World Geodetic System 1984 ensemble
- Ellipsoid: WGS 84
- Prime Meridian: Greenwich
"""
return self.geometry.estimate_utm_crs(datum_name=datum_name)
def __getitem__(self, key):
"""
If the result is a column containing only 'geometry', return a
GeoSeries. If it's a DataFrame with any columns of GeometryDtype,
return a GeoDataFrame.
"""
result = super().__getitem__(key)
# Custom logic to avoid waiting for pandas GH51895
# result is not geometry dtype for multi-indexes
if (
pd.api.types.is_scalar(key)
and key == ""
and isinstance(self.columns, pd.MultiIndex)
and isinstance(result, Series)
and not is_geometry_type(result)
):
loc = self.columns.get_loc(key)
# squeeze stops multilevel columns from returning a gdf
result = self.iloc[:, loc].squeeze(axis="columns")
geo_col = self._geometry_column_name
if isinstance(result, Series) and isinstance(result.dtype, GeometryDtype):
result.__class__ = GeoSeries
elif isinstance(result, DataFrame):
if (result.dtypes == "geometry").sum() > 0:
result.__class__ = GeoDataFrame
if geo_col in result:
result._geometry_column_name = geo_col
else:
result.__class__ = DataFrame
return result
def _persist_old_default_geometry_colname(self):
"""Internal util to temporarily persist the default geometry column
name of 'geometry' for backwards compatibility."""
# self.columns check required to avoid this warning in __init__
if self._geometry_column_name is None and "geometry" not in self.columns:
msg = (
"You are adding a column named 'geometry' to a GeoDataFrame "
"constructed without an active geometry column. Currently, "
"this automatically sets the active geometry column to 'geometry' "
"but in the future that will no longer happen. Instead, either "
"provide geometry to the GeoDataFrame constructor "
"(GeoDataFrame(... geometry=GeoSeries()) or use "
"`set_geometry('geometry')` "
"to explicitly set the active geometry column."
)
warnings.warn(msg, category=FutureWarning, stacklevel=3)
self._geometry_column_name = "geometry"
def __setitem__(self, key, value):
"""
Overwritten to preserve CRS of GeometryArray in cases like
df['geometry'] = [geom... for geom in df.geometry]
"""
if not pd.api.types.is_list_like(key) and (
key == self._geometry_column_name
or key == "geometry"
and self._geometry_column_name is None
):
if pd.api.types.is_scalar(value) or isinstance(value, BaseGeometry):
value = [value] * self.shape[0]
try:
if self._geometry_column_name is not None:
crs = getattr(self, "crs", None)
else: # don't use getattr, because a col "crs" might exist
crs = None
value = _ensure_geometry(value, crs=crs)
if key == "geometry":
self._persist_old_default_geometry_colname()
except TypeError:
warnings.warn(
"Geometry column does not contain geometry.",
stacklevel=2,
)
super().__setitem__(key, value)
#
# Implement pandas methods
#
@doc(pd.DataFrame)
def copy(self, deep=True):
copied = super().copy(deep=deep)
if type(copied) is pd.DataFrame:
copied.__class__ = GeoDataFrame
copied._geometry_column_name = self._geometry_column_name
return copied
@doc(pd.DataFrame)
def apply(self, func, axis=0, raw=False, result_type=None, args=(), **kwargs):
result = super().apply(
func, axis=axis, raw=raw, result_type=result_type, args=args, **kwargs
)
# Reconstruct gdf if it was lost by apply
if (
isinstance(result, DataFrame)
and self._geometry_column_name in result.columns
):
# axis=1 apply will split GeometryDType to object, try and cast back
try:
result = result.set_geometry(self._geometry_column_name)
except TypeError:
pass
else:
if self.crs is not None and result.crs is None:
result.set_crs(self.crs, inplace=True)
elif isinstance(result, Series) and result.dtype == "object":
# Try reconstruct series GeometryDtype if lost by apply
# If all none and object dtype assert list of nones is more likely
# intended than list of null geometry.
if not result.isna().all():
try:
# not enough info about func to preserve CRS
result = _ensure_geometry(result)
except (TypeError, shapely.errors.GeometryTypeError):
pass
return result
@property
def _constructor(self):
return _geodataframe_constructor_with_fallback
def _constructor_from_mgr(self, mgr, axes):
# replicate _geodataframe_constructor_with_fallback behaviour
# unless safe to skip
if not any(isinstance(block.dtype, GeometryDtype) for block in mgr.blocks):
return _geodataframe_constructor_with_fallback(
pd.DataFrame._from_mgr(mgr, axes)
)
gdf = GeoDataFrame._from_mgr(mgr, axes)
# _from_mgr doesn't preserve metadata (expect __finalize__ to be called)
# still need to mimic __init__ behaviour with geometry=None
if (gdf.columns == "geometry").sum() == 1: # only if "geometry" is single col
gdf._geometry_column_name = "geometry"
return gdf
@property
def _constructor_sliced(self):
def _geodataframe_constructor_sliced(*args, **kwargs):
"""
A specialized (Geo)Series constructor which can fall back to a
Series if a certain operation does not produce geometries:
- We only return a GeoSeries if the data is actually of geometry
dtype (and so we don't try to convert geometry objects such as
the normal GeoSeries(..) constructor does with `_ensure_geometry`).
- When we get here from obtaining a row or column from a
GeoDataFrame, the goal is to only return a GeoSeries for a
geometry column, and not return a GeoSeries for a row that happened
to come from a DataFrame with only geometry dtype columns (and
thus could have a geometry dtype). Therefore, we don't return a
GeoSeries if we are sure we are in a row selection case (by
checking the identity of the index)
"""
srs = pd.Series(*args, **kwargs)
is_row_proxy = srs.index.is_(self.columns)
if is_geometry_type(srs) and not is_row_proxy:
srs = GeoSeries(srs)
return srs
return _geodataframe_constructor_sliced
def _constructor_sliced_from_mgr(self, mgr, axes):
is_row_proxy = mgr.index.is_(self.columns)
if isinstance(mgr.blocks[0].dtype, GeometryDtype) and not is_row_proxy:
return GeoSeries._from_mgr(mgr, axes)
return Series._from_mgr(mgr, axes)
def __finalize__(self, other, method=None, **kwargs):
"""propagate metadata from other to self"""
self = super().__finalize__(other, method=method, **kwargs)
# merge operation: using metadata of the left object
if method == "merge":
for name in self._metadata:
object.__setattr__(self, name, getattr(other.left, name, None))
# concat operation: using metadata of the first object
elif method == "concat":
for name in self._metadata:
object.__setattr__(self, name, getattr(other.objs[0], name, None))
if (self.columns == self._geometry_column_name).sum() > 1:
raise ValueError(
"Concat operation has resulted in multiple columns using "
f"the geometry column name '{self._geometry_column_name}'.\n"
"Please ensure this column from the first DataFrame is not "
"repeated."
)
elif method == "unstack":
# unstack adds multiindex columns and reshapes data.
# it never makes sense to retain geometry column
self._geometry_column_name = None
self._crs = None
return self
def dissolve(
self,
by=None,
aggfunc="first",
as_index=True,
level=None,
sort=True,
observed=False,
dropna=True,
method="unary",
**kwargs,
):
"""
Dissolve geometries within `groupby` into single observation.
This is accomplished by applying the `union_all` method
to all geometries within a groupself.
Observations associated with each `groupby` group will be aggregated
using the `aggfunc`.
Parameters
----------
by : str or list-like, default None
Column(s) whose values define the groups to be dissolved. If None,
the entire GeoDataFrame is considered as a single group. If a list-like
object is provided, the values in the list are treated as categorical
labels, and polygons will be combined based on the equality of
these categorical labels.
aggfunc : function or string, default "first"
Aggregation function for manipulation of data associated
with each group. Passed to pandas `groupby.agg` method.
Accepted combinations are:
- function
- string function name
- list of functions and/or function names, e.g. [np.sum, 'mean']
- dict of axis labels -> functions, function names or list of such.
as_index : boolean, default True
If true, groupby columns become index of result.
level : int or str or sequence of int or sequence of str, default None
If the axis is a MultiIndex (hierarchical), group by a
particular level or levels.
sort : bool, default True
Sort group keys. Get better performance by turning this off.
Note this does not influence the order of observations within
each group. Groupby preserves the order of rows within each group.
observed : bool, default False
This only applies if any of the groupers are Categoricals.
If True: only show observed values for categorical groupers.
If False: show all values for categorical groupers.
dropna : bool, default True
If True, and if group keys contain NA values, NA values
together with row/column will be dropped. If False, NA
values will also be treated as the key in groups.
method : str (default ``"unary"``)
The method to use for the union. Options are:
* ``"unary"``: use the unary union algorithm. This option is the most robust
but can be slow for large numbers of geometries (default).
* ``"coverage"``: use the coverage union algorithm. This option is optimized
for non-overlapping polygons and can be significantly faster than the
unary union algorithm. However, it can produce invalid geometries if the
polygons overlap.
**kwargs :
Keyword arguments to be passed to the pandas `DataFrameGroupby.agg` method
which is used by `dissolve`. In particular, `numeric_only` may be
supplied, which will be required in pandas 2.0 for certain aggfuncs.
.. versionadded:: 0.13.0
Returns
-------
GeoDataFrame
Examples
--------
>>> from shapely.geometry import Point
>>> d = {
... "col1": ["name1", "name2", "name1"],
... "geometry": [Point(1, 2), Point(2, 1), Point(0, 1)],
... }
>>> gdf = geopandas.GeoDataFrame(d, crs=4326)
>>> gdf
col1 geometry
0 name1 POINT (1 2)
1 name2 POINT (2 1)
2 name1 POINT (0 1)
>>> dissolved = gdf.dissolve('col1')
>>> dissolved # doctest: +SKIP
geometry
col1
name1 MULTIPOINT ((0 1), (1 2))
name2 POINT (2 1)
See also
--------
GeoDataFrame.explode : explode multi-part geometries into single geometries
"""
if by is None and level is None:
by = np.zeros(len(self), dtype="int64")
groupby_kwargs = {
"by": by,
"level": level,
"sort": sort,
"observed": observed,
"dropna": dropna,
}
# Process non-spatial component
data = self.drop(labels=self.geometry.name, axis=1)
with warnings.catch_warnings(record=True) as record:
aggregated_data = data.groupby(**groupby_kwargs).agg(aggfunc, **kwargs)
for w in record:
if str(w.message).startswith("The default value of numeric_only"):
msg = (
f"The default value of numeric_only in aggfunc='{aggfunc}' "
"within pandas.DataFrameGroupBy.agg used in dissolve is "
"deprecated. In pandas 2.0, numeric_only will default to False. "
"Either specify numeric_only as additional argument in dissolve() "
"or select only columns which should be valid for the function."
)
warnings.warn(msg, FutureWarning, stacklevel=2)
else:
# Only want to capture specific warning,
# other warnings from pandas should be passed through
# TODO this is not an ideal approach
warnings.showwarning(
w.message, w.category, w.filename, w.lineno, w.file, w.line
)
aggregated_data.columns = aggregated_data.columns.to_flat_index()
# Process spatial component
def merge_geometries(block):
merged_geom = block.union_all(method=method)
return merged_geom
g = self.groupby(group_keys=False, **groupby_kwargs)[self.geometry.name].agg(
merge_geometries
)
# Aggregate
aggregated_geometry = GeoDataFrame(g, geometry=self.geometry.name, crs=self.crs)
# Recombine
aggregated = aggregated_geometry.join(aggregated_data)
# Reset if requested
if not as_index:
aggregated = aggregated.reset_index()
return aggregated
# overrides the pandas native explode method to break up features geometrically
def explode(self, column=None, ignore_index=False, index_parts=False, **kwargs):
"""
Explode multi-part geometries into multiple single geometries.
Each row containing a multi-part geometry will be split into
multiple rows with single geometries, thereby increasing the vertical
size of the GeoDataFrame.
Parameters
----------
column : string, default None
Column to explode. In the case of a geometry column, multi-part
geometries are converted to single-part.
If None, the active geometry column is used.
ignore_index : bool, default False
If True, the resulting index will be labelled 0, 1, …, n - 1,
ignoring `index_parts`.
index_parts : boolean, default False
If True, the resulting index will be a multi-index (original
index with an additional level indicating the multiple
geometries: a new zero-based index for each single part geometry
per multi-part geometry).
Returns
-------
GeoDataFrame
Exploded geodataframe with each single geometry
as a separate entry in the geodataframe.
Examples
--------
>>> from shapely.geometry import MultiPoint
>>> d = {
... "col1": ["name1", "name2"],
... "geometry": [
... MultiPoint([(1, 2), (3, 4)]),
... MultiPoint([(2, 1), (0, 0)]),
... ],
... }
>>> gdf = geopandas.GeoDataFrame(d, crs=4326)
>>> gdf
col1 geometry
0 name1 MULTIPOINT ((1 2), (3 4))
1 name2 MULTIPOINT ((2 1), (0 0))
>>> exploded = gdf.explode(index_parts=True)
>>> exploded
col1 geometry
0 0 name1 POINT (1 2)
1 name1 POINT (3 4)
1 0 name2 POINT (2 1)
1 name2 POINT (0 0)
>>> exploded = gdf.explode(index_parts=False)
>>> exploded
col1 geometry
0 name1 POINT (1 2)
0 name1 POINT (3 4)
1 name2 POINT (2 1)
1 name2 POINT (0 0)
>>> exploded = gdf.explode(ignore_index=True)
>>> exploded
col1 geometry
0 name1 POINT (1 2)
1 name1 POINT (3 4)
2 name2 POINT (2 1)
3 name2 POINT (0 0)
See also
--------
GeoDataFrame.dissolve : dissolve geometries into a single observation.
"""
# If no column is specified then default to the active geometry column
if column is None:
column = self.geometry.name
# If the specified column is not a geometry dtype use pandas explode
if not isinstance(self[column].dtype, GeometryDtype):
return super().explode(column, ignore_index=ignore_index, **kwargs)
exploded_geom = self.geometry.reset_index(drop=True).explode(index_parts=True)
df = self.drop(self._geometry_column_name, axis=1).take(
exploded_geom.index.droplevel(-1)
)
df[exploded_geom.name] = exploded_geom.values
df = df.set_geometry(self._geometry_column_name).__finalize__(self)
if ignore_index:
df.reset_index(inplace=True, drop=True)
elif index_parts:
# reset to MultiIndex, otherwise df index is only first level of
# exploded GeoSeries index.
df = df.set_index(
exploded_geom.index.droplevel(
list(range(exploded_geom.index.nlevels - 1))
),
append=True,
)
return df
# overrides the pandas astype method to ensure the correct return type
# should be removable when pandas 1.4 is dropped
def astype(self, dtype, copy=None, errors="raise", **kwargs):
"""
Cast a pandas object to a specified dtype ``dtype``.
Returns a GeoDataFrame when the geometry column is kept as geometries,
otherwise returns a pandas DataFrame.
See the pandas.DataFrame.astype docstring for more details.
Returns
-------
GeoDataFrame or DataFrame
"""
if not PANDAS_GE_30 and copy is None:
copy = True
if copy is not None:
kwargs["copy"] = copy
df = super().astype(dtype, errors=errors, **kwargs)
try:
geoms = df[self._geometry_column_name]
if is_geometry_type(geoms):
return geopandas.GeoDataFrame(df, geometry=self._geometry_column_name)
except KeyError:
pass
# if the geometry column is converted to non-geometries or did not exist
# do not return a GeoDataFrame
return pd.DataFrame(df)
def to_postgis(
self,
name,
con,
schema=None,
if_exists="fail",
index=False,
index_label=None,
chunksize=None,
dtype=None,
):
"""
Upload GeoDataFrame into PostGIS database.
This method requires SQLAlchemy and GeoAlchemy2, and a PostgreSQL
Python driver (psycopg or psycopg2) to be installed.
It is also possible to use :meth:`~GeoDataFrame.to_file` to write to a database.
Especially for file geodatabases like GeoPackage or SpatiaLite this can be
easier.
Parameters
----------
name : str
Name of the target table.
con : sqlalchemy.engine.Connection or sqlalchemy.engine.Engine
Active connection to the PostGIS database.
if_exists : {'fail', 'replace', 'append'}, default 'fail'
How to behave if the table already exists:
- fail: Raise a ValueError.
- replace: Drop the table before inserting new values.
- append: Insert new values to the existing table.
schema : string, optional
Specify the schema. If None, use default schema: 'public'.
index : bool, default False
Write DataFrame index as a column.
Uses *index_label* as the column name in the table.
index_label : string or sequence, default None
Column label for index column(s).
If None is given (default) and index is True,
then the index names are used.
chunksize : int, optional
Rows will be written in batches of this size at a time.
By default, all rows will be written at once.
dtype : dict of column name to SQL type, default None
Specifying the datatype for columns.
The keys should be the column names and the values
should be the SQLAlchemy types.
Examples
--------
>>> from sqlalchemy import create_engine
>>> engine = create_engine("postgresql://myusername:mypassword@myhost:5432\
/mydatabase") # doctest: +SKIP
>>> gdf.to_postgis("my_table", engine) # doctest: +SKIP
See also
--------
GeoDataFrame.to_file : write GeoDataFrame to file
read_postgis : read PostGIS database to GeoDataFrame
"""
geopandas.io.sql._write_postgis(
self, name, con, schema, if_exists, index, index_label, chunksize, dtype
)
plot = Accessor("plot", geopandas.plotting.GeoplotAccessor)
@doc(_explore)
def explore(self, *args, **kwargs):
return _explore(self, *args, **kwargs)
def sjoin(self, df, *args, **kwargs):
"""Spatial join of two GeoDataFrames.
See the User Guide page :doc:`../../user_guide/mergingdata` for details.
Parameters
----------
df : GeoDataFrame
how : string, default 'inner'
The type of join:
* 'left': use keys from left_df; retain only left_df geometry column
* 'right': use keys from right_df; retain only right_df geometry column
* 'inner': use intersection of keys from both dfs; retain only
left_df geometry column
predicate : string, default 'intersects'
Binary predicate. Valid values are determined by the spatial index used.
You can check the valid values in left_df or right_df as
``left_df.sindex.valid_query_predicates`` or
``right_df.sindex.valid_query_predicates``
lsuffix : string, default 'left'
Suffix to apply to overlapping column names (left GeoDataFrame).
rsuffix : string, default 'right'
Suffix to apply to overlapping column names (right GeoDataFrame).
distance : number or array_like, optional
Distance(s) around each input geometry within which to query the tree
for the 'dwithin' predicate. If array_like, must be
one-dimesional with length equal to length of left GeoDataFrame.
Required if ``predicate='dwithin'``.
on_attribute : string, list or tuple
Column name(s) to join on as an additional join restriction on top
of the spatial predicate. These must be found in both DataFrames.
If set, observations are joined only if the predicate applies
and values in specified columns match.
Examples
--------
>>> import geodatasets
>>> chicago = geopandas.read_file(
... geodatasets.get_path("geoda.chicago_commpop")
... )
>>> groceries = geopandas.read_file(
... geodatasets.get_path("geoda.groceries")
... ).to_crs(chicago.crs)
>>> chicago.head() # doctest: +SKIP
community ... geometry
0 DOUGLAS ... MULTIPOLYGON (((-87.60914 41.84469, -87.60915 ...
1 OAKLAND ... MULTIPOLYGON (((-87.59215 41.81693, -87.59231 ...
2 FULLER PARK ... MULTIPOLYGON (((-87.62880 41.80189, -87.62879 ...
3 GRAND BOULEVARD ... MULTIPOLYGON (((-87.60671 41.81681, -87.60670 ...
4 KENWOOD ... MULTIPOLYGON (((-87.59215 41.81693, -87.59215 ...
[5 rows x 9 columns]
>>> groceries.head() # doctest: +SKIP
OBJECTID Ycoord ... Category geometry
0 16 41.973266 ... NaN MULTIPOINT ((-87.65661 41.97321))
1 18 41.696367 ... NaN MULTIPOINT ((-87.68136 41.69713))
2 22 41.868634 ... NaN MULTIPOINT ((-87.63918 41.86847))
3 23 41.877590 ... new MULTIPOINT ((-87.65495 41.87783))
4 27 41.737696 ... NaN MULTIPOINT ((-87.62715 41.73623))
[5 rows x 8 columns]
>>> groceries_w_communities = groceries.sjoin(chicago)
>>> groceries_w_communities[["OBJECTID", "community", "geometry"]].head()
OBJECTID community geometry
0 16 UPTOWN MULTIPOINT ((-87.65661 41.97321))
1 18 MORGAN PARK MULTIPOINT ((-87.68136 41.69713))
2 22 NEAR WEST SIDE MULTIPOINT ((-87.63918 41.86847))
3 23 NEAR WEST SIDE MULTIPOINT ((-87.65495 41.87783))
4 27 CHATHAM MULTIPOINT ((-87.62715 41.73623))
Notes
-----
Every operation in GeoPandas is planar, i.e. the potential third
dimension is not taken into account.
See also
--------
GeoDataFrame.sjoin_nearest : nearest neighbor join
sjoin : equivalent top-level function
"""
return geopandas.sjoin(left_df=self, right_df=df, *args, **kwargs) # noqa: B026
def sjoin_nearest(
self,
right,
how="inner",
max_distance=None,
lsuffix="left",
rsuffix="right",
distance_col=None,
exclusive=False,
):
"""
Spatial join of two GeoDataFrames based on the distance between their
geometries.
Results will include multiple output records for a single input record
where there are multiple equidistant nearest or intersected neighbors.
See the User Guide page
https://geopandas.readthedocs.io/en/latest/docs/user_guide/mergingdata.html
for more details.
Parameters
----------
right : GeoDataFrame
how : string, default 'inner'
The type of join:
* 'left': use keys from left_df; retain only left_df geometry column
* 'right': use keys from right_df; retain only right_df geometry column
* 'inner': use intersection of keys from both dfs; retain only
left_df geometry column
max_distance : float, default None
Maximum distance within which to query for nearest geometry.
Must be greater than 0.
The max_distance used to search for nearest items in the tree may have a
significant impact on performance by reducing the number of input
geometries that are evaluated for nearest items in the tree.
lsuffix : string, default 'left'
Suffix to apply to overlapping column names (left GeoDataFrame).
rsuffix : string, default 'right'
Suffix to apply to overlapping column names (right GeoDataFrame).
distance_col : string, default None
If set, save the distances computed between matching geometries under a
column of this name in the joined GeoDataFrame.
exclusive : bool, optional, default False
If True, the nearest geometries that are equal to the input geometry
will not be returned, default False.
Requires Shapely >= 2.0
Examples
--------
>>> import geodatasets
>>> groceries = geopandas.read_file(
... geodatasets.get_path("geoda.groceries")
... )
>>> chicago = geopandas.read_file(
... geodatasets.get_path("geoda.chicago_health")
... ).to_crs(groceries.crs)
>>> chicago.head() # doctest: +SKIP
ComAreaID ... geometry
0 35 ... POLYGON ((-87.60914 41.84469, -87.60915 41.844...
1 36 ... POLYGON ((-87.59215 41.81693, -87.59231 41.816...
2 37 ... POLYGON ((-87.62880 41.80189, -87.62879 41.801...
3 38 ... POLYGON ((-87.60671 41.81681, -87.60670 41.816...
4 39 ... POLYGON ((-87.59215 41.81693, -87.59215 41.816...
[5 rows x 87 columns]
>>> groceries.head() # doctest: +SKIP
OBJECTID Ycoord ... Category geometry
0 16 41.973266 ... NaN MULTIPOINT ((-87.65661 41.97321))
1 18 41.696367 ... NaN MULTIPOINT ((-87.68136 41.69713))
2 22 41.868634 ... NaN MULTIPOINT ((-87.63918 41.86847))
3 23 41.877590 ... new MULTIPOINT ((-87.65495 41.87783))
4 27 41.737696 ... NaN MULTIPOINT ((-87.62715 41.73623))
[5 rows x 8 columns]
>>> groceries_w_communities = groceries.sjoin_nearest(chicago)
>>> groceries_w_communities[["Chain", "community", "geometry"]].head(2)
Chain community geometry
0 VIET HOA PLAZA UPTOWN MULTIPOINT ((1168268.672 1933554.35))
1 COUNTY FAIR FOODS MORGAN PARK MULTIPOINT ((1162302.618 1832900.224))
To include the distances:
>>> groceries_w_communities = groceries.sjoin_nearest(chicago, \
distance_col="distances")
>>> groceries_w_communities[["Chain", "community", \
"distances"]].head(2)
Chain community distances
0 VIET HOA PLAZA UPTOWN 0.0
1 COUNTY FAIR FOODS MORGAN PARK 0.0
In the following example, we get multiple groceries for Uptown because all
results are equidistant (in this case zero because they intersect).
In fact, we get 4 results in total:
>>> chicago_w_groceries = groceries.sjoin_nearest(chicago, \
distance_col="distances", how="right")
>>> uptown_results = \
chicago_w_groceries[chicago_w_groceries["community"] == "UPTOWN"]
>>> uptown_results[["Chain", "community"]]
Chain community
30 VIET HOA PLAZA UPTOWN
30 JEWEL OSCO UPTOWN
30 TARGET UPTOWN
30 Mariano's UPTOWN
See also
--------
GeoDataFrame.sjoin : binary predicate joins
sjoin_nearest : equivalent top-level function
Notes
-----
Since this join relies on distances, results will be inaccurate
if your geometries are in a geographic CRS.
Every operation in GeoPandas is planar, i.e. the potential third
dimension is not taken into account.
"""
return geopandas.sjoin_nearest(
self,
right,
how=how,
max_distance=max_distance,
lsuffix=lsuffix,
rsuffix=rsuffix,
distance_col=distance_col,
exclusive=exclusive,
)
def clip(self, mask, keep_geom_type=False, sort=False):
"""Clip points, lines, or polygon geometries to the mask extent.
Both layers must be in the same Coordinate Reference System (CRS).
The GeoDataFrame will be clipped to the full extent of the ``mask`` object.
If there are multiple polygons in mask, data from the GeoDataFrame will be
clipped to the total boundary of all polygons in mask.
Parameters
----------
mask : GeoDataFrame, GeoSeries, (Multi)Polygon, list-like
Polygon vector layer used to clip the GeoDataFrame.
The mask's geometry is dissolved into one geometric feature
and intersected with GeoDataFrame.
If the mask is list-like with four elements ``(minx, miny, maxx, maxy)``,
``clip`` will use a faster rectangle clipping
(:meth:`~GeoSeries.clip_by_rect`), possibly leading to slightly different
results.
keep_geom_type : boolean, default False
If True, return only geometries of original type in case of intersection
resulting in multiple geometry types or GeometryCollections.
If False, return all resulting geometries (potentially mixed types).
sort : boolean, default False
If True, the order of rows in the clipped GeoDataFrame will be preserved at
small performance cost. If False the order of rows in the clipped
GeoDataFrame will be random.
Returns
-------
GeoDataFrame
Vector data (points, lines, polygons) from the GeoDataFrame clipped to
polygon boundary from mask.
See also
--------
clip : equivalent top-level function
Examples
--------
Clip points (grocery stores) with polygons (the Near West Side community):
>>> import geodatasets
>>> chicago = geopandas.read_file(
... geodatasets.get_path("geoda.chicago_health")
... )
>>> near_west_side = chicago[chicago["community"] == "NEAR WEST SIDE"]
>>> groceries = geopandas.read_file(
... geodatasets.get_path("geoda.groceries")
... ).to_crs(chicago.crs)
>>> groceries.shape
(148, 8)
>>> nws_groceries = groceries.clip(near_west_side)
>>> nws_groceries.shape
(7, 8)
"""
return geopandas.clip(self, mask=mask, keep_geom_type=keep_geom_type, sort=sort)
def overlay(self, right, how="intersection", keep_geom_type=None, make_valid=True):
"""Perform spatial overlay between GeoDataFrames.
Currently only supports data GeoDataFrames with uniform geometry types,
i.e. containing only (Multi)Polygons, or only (Multi)Points, or a
combination of (Multi)LineString and LinearRing shapes.
Implements several methods that are all effectively subsets of the union.
See the User Guide page :doc:`../../user_guide/set_operations` for details.
Parameters
----------
right : GeoDataFrame
how : string
Method of spatial overlay: 'intersection', 'union',
'identity', 'symmetric_difference' or 'difference'.
keep_geom_type : bool
If True, return only geometries of the same geometry type the GeoDataFrame
has, if False, return all resulting geometries. Default is None,
which will set keep_geom_type to True but warn upon dropping
geometries.
make_valid : bool, default True
If True, any invalid input geometries are corrected with a call to
make_valid(), if False, a `ValueError` is raised if any input geometries
are invalid.
Returns
-------
df : GeoDataFrame
GeoDataFrame with new set of polygons and attributes
resulting from the overlay
Examples
--------
>>> from shapely.geometry import Polygon
>>> polys1 = geopandas.GeoSeries([Polygon([(0,0), (2,0), (2,2), (0,2)]),
... Polygon([(2,2), (4,2), (4,4), (2,4)])])
>>> polys2 = geopandas.GeoSeries([Polygon([(1,1), (3,1), (3,3), (1,3)]),
... Polygon([(3,3), (5,3), (5,5), (3,5)])])
>>> df1 = geopandas.GeoDataFrame({'geometry': polys1, 'df1_data':[1,2]})
>>> df2 = geopandas.GeoDataFrame({'geometry': polys2, 'df2_data':[1,2]})
>>> df1.overlay(df2, how='union')
df1_data df2_data geometry
0 1.0 1.0 POLYGON ((2 2, 2 1, 1 1, 1 2, 2 2))
1 2.0 1.0 POLYGON ((2 2, 2 3, 3 3, 3 2, 2 2))
2 2.0 2.0 POLYGON ((4 4, 4 3, 3 3, 3 4, 4 4))
3 1.0 NaN POLYGON ((2 0, 0 0, 0 2, 1 2, 1 1, 2 1, 2 0))
4 2.0 NaN MULTIPOLYGON (((3 4, 3 3, 2 3, 2 4, 3 4)), ((4...
5 NaN 1.0 MULTIPOLYGON (((2 3, 2 2, 1 2, 1 3, 2 3)), ((3...
6 NaN 2.0 POLYGON ((3 5, 5 5, 5 3, 4 3, 4 4, 3 4, 3 5))
>>> df1.overlay(df2, how='intersection')
df1_data df2_data geometry
0 1 1 POLYGON ((2 2, 2 1, 1 1, 1 2, 2 2))
1 2 1 POLYGON ((2 2, 2 3, 3 3, 3 2, 2 2))
2 2 2 POLYGON ((4 4, 4 3, 3 3, 3 4, 4 4))
>>> df1.overlay(df2, how='symmetric_difference')
df1_data df2_data geometry
0 1.0 NaN POLYGON ((2 0, 0 0, 0 2, 1 2, 1 1, 2 1, 2 0))
1 2.0 NaN MULTIPOLYGON (((3 4, 3 3, 2 3, 2 4, 3 4)), ((4...
2 NaN 1.0 MULTIPOLYGON (((2 3, 2 2, 1 2, 1 3, 2 3)), ((3...
3 NaN 2.0 POLYGON ((3 5, 5 5, 5 3, 4 3, 4 4, 3 4, 3 5))
>>> df1.overlay(df2, how='difference')
geometry df1_data
0 POLYGON ((2 0, 0 0, 0 2, 1 2, 1 1, 2 1, 2 0)) 1
1 MULTIPOLYGON (((3 4, 3 3, 2 3, 2 4, 3 4)), ((4... 2
>>> df1.overlay(df2, how='identity')
df1_data df2_data geometry
0 1.0 1.0 POLYGON ((2 2, 2 1, 1 1, 1 2, 2 2))
1 2.0 1.0 POLYGON ((2 2, 2 3, 3 3, 3 2, 2 2))
2 2.0 2.0 POLYGON ((4 4, 4 3, 3 3, 3 4, 4 4))
3 1.0 NaN POLYGON ((2 0, 0 0, 0 2, 1 2, 1 1, 2 1, 2 0))
4 2.0 NaN MULTIPOLYGON (((3 4, 3 3, 2 3, 2 4, 3 4)), ((4...
See also
--------
GeoDataFrame.sjoin : spatial join
overlay : equivalent top-level function
Notes
-----
Every operation in GeoPandas is planar, i.e. the potential third
dimension is not taken into account.
"""
return geopandas.overlay(
self, right, how=how, keep_geom_type=keep_geom_type, make_valid=make_valid
)
def _dataframe_set_geometry(self, col, drop=None, inplace=False, crs=None):
if inplace:
raise ValueError(
"Can't do inplace setting when converting from DataFrame to GeoDataFrame"
)
gf = GeoDataFrame(self)
# this will copy so that BlockManager gets copied
return gf.set_geometry(col, drop=drop, inplace=False, crs=crs)
DataFrame.set_geometry = _dataframe_set_geometry