Note
Plotting with Geoplot and GeoPandas#
Geoplot is a Python library providing a selection of easy-to-use geospatial visualizations. It is built on top of the lower-level CartoPy, covered in a separate section of this tutorial, and is designed to work with GeoPandas input.
This example is a brief tour of the geoplot API. For more details on the library refer to its documentation.
First we’ll load in the data using GeoPandas.
[1]:
import geopandas
import geodatasets
import geoplot
world = geopandas.read_file("https://naciscdn.org/naturalearth/110m/cultural/ne_110m_admin_0_countries.zip")
boroughs = geopandas.read_file(geoplot.datasets.get_path("nyc_boroughs"))
collisions = geopandas.read_file(geoplot.datasets.get_path("nyc_injurious_collisions"))
Plotting with Geoplot#
We start out by replicating the basic GeoPandas world plot using Geoplot.
[2]:
geoplot.polyplot(world, figsize=(8, 4))
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/geoplot/geoplot.py:885, in polyplot.<locals>.PolyPlot.draw(self)
884 try: # Duck test for MultiPolygon.
--> 885 for subgeom in geom:
886 feature = GeopandasPolygonPatch(
887 subgeom, facecolor=facecolor, edgecolor=edgecolor, zorder=zorder,
888 **kwargs
889 )
TypeError: 'MultiPolygon' object is not iterable
During handling of the above exception, another exception occurred:
AttributeError Traceback (most recent call last)
Cell In[2], line 1
----> 1 geoplot.polyplot(world, figsize=(8, 4))
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/geoplot/geoplot.py:901, in polyplot(df, projection, extent, figsize, ax, **kwargs)
898 return ax
900 plot = PolyPlot(df, figsize=figsize, ax=ax, extent=extent, projection=projection, **kwargs)
--> 901 return plot.draw()
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/geoplot/geoplot.py:892, in polyplot.<locals>.PolyPlot.draw(self)
890 ax.add_patch(feature)
891 except (TypeError, AssertionError): # Shapely Polygon.
--> 892 feature = GeopandasPolygonPatch(
893 geom, facecolor=facecolor, edgecolor=edgecolor, zorder=zorder,
894 **kwargs
895 )
896 ax.add_patch(feature)
898 return ax
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/geopandas/plotting.py:129, in _PolygonPatch(polygon, **kwargs)
125 from matplotlib.patches import PathPatch
126 from matplotlib.path import Path
128 path = Path.make_compound_path(
--> 129 Path(np.asarray(polygon.exterior.coords)[:, :2]),
130 *[Path(np.asarray(ring.coords)[:, :2]) for ring in polygon.interiors],
131 )
132 return PathPatch(path, **kwargs)
AttributeError: 'MultiPolygon' object has no attribute 'exterior'
Geoplot can re-project data into any of the map projections provided by CartoPy (see the list here).
[3]:
# use the Orthographic map projection (e.g. a world globe)
ax = geoplot.polyplot(world, projection=geoplot.crs.Orthographic(), figsize=(8, 4))
ax.outline_patch.set_visible(True)
/home/docs/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/geoplot/geoplot.py:703: UserWarning: Plot extent lies outside of the Orthographic projection's viewport. Defaulting to global extent.
warnings.warn(
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
Cell In[3], line 3
1 # use the Orthographic map projection (e.g. a world globe)
2 ax = geoplot.polyplot(world, projection=geoplot.crs.Orthographic(), figsize=(8, 4))
----> 3 ax.outline_patch.set_visible(True)
AttributeError: 'GeoAxes' object has no attribute 'outline_patch'
polyplot is trivial and can only plot the geometries you pass to it. If you want to use color as a visual variable, specify a choropleth. Here we sort GDP per person by country into five buckets by color, using “quantiles” binning from the Mapclassify library.
[4]:
import mapclassify
gpd_per_person = world["gdp_md_est"] / world["pop_est"]
scheme = mapclassify.Quantiles(gpd_per_person, k=5)
# Note: this code sample requires geoplot>=0.4.0.
geoplot.choropleth(
world, hue=gpd_per_person, scheme=scheme, cmap="Greens", figsize=(8, 4)
)
---------------------------------------------------------------------------
KeyError Traceback (most recent call last)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/indexes/base.py:3652, in Index.get_loc(self, key)
3651 try:
-> 3652 return self._engine.get_loc(casted_key)
3653 except KeyError as err:
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/_libs/index.pyx:147, in pandas._libs.index.IndexEngine.get_loc()
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/_libs/index.pyx:176, in pandas._libs.index.IndexEngine.get_loc()
File pandas/_libs/hashtable_class_helper.pxi:7080, in pandas._libs.hashtable.PyObjectHashTable.get_item()
File pandas/_libs/hashtable_class_helper.pxi:7088, in pandas._libs.hashtable.PyObjectHashTable.get_item()
KeyError: 'gdp_md_est'
The above exception was the direct cause of the following exception:
KeyError Traceback (most recent call last)
Cell In[4], line 3
1 import mapclassify
----> 3 gpd_per_person = world["gdp_md_est"] / world["pop_est"]
4 scheme = mapclassify.Quantiles(gpd_per_person, k=5)
6 # Note: this code sample requires geoplot>=0.4.0.
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/geopandas/geodataframe.py:1475, in GeoDataFrame.__getitem__(self, key)
1469 def __getitem__(self, key):
1470 """
1471 If the result is a column containing only 'geometry', return a
1472 GeoSeries. If it's a DataFrame with any columns of GeometryDtype,
1473 return a GeoDataFrame.
1474 """
-> 1475 result = super().__getitem__(key)
1476 # Custom logic to avoid waiting for pandas GH51895
1477 # result is not geometry dtype for multi-indexes
1478 if (
1479 pd.api.types.is_scalar(key)
1480 and key == ""
(...)
1483 and not is_geometry_type(result)
1484 ):
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/frame.py:3761, in DataFrame.__getitem__(self, key)
3759 if self.columns.nlevels > 1:
3760 return self._getitem_multilevel(key)
-> 3761 indexer = self.columns.get_loc(key)
3762 if is_integer(indexer):
3763 indexer = [indexer]
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/indexes/base.py:3654, in Index.get_loc(self, key)
3652 return self._engine.get_loc(casted_key)
3653 except KeyError as err:
-> 3654 raise KeyError(key) from err
3655 except TypeError:
3656 # If we have a listlike key, _check_indexing_error will raise
3657 # InvalidIndexError. Otherwise we fall through and re-raise
3658 # the TypeError.
3659 self._check_indexing_error(key)
KeyError: 'gdp_md_est'
If you want to use size as a visual variable, use a cartogram. Here are population estimates for countries in Africa.
[5]:
africa = world.query('continent == "Africa"')
ax = geoplot.cartogram(
africa, scale="pop_est", limits=(0.2, 1), edgecolor="None", figsize=(7, 8)
)
geoplot.polyplot(africa, edgecolor="gray", ax=ax)
---------------------------------------------------------------------------
KeyError Traceback (most recent call last)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/scope.py:233, in Scope.resolve(self, key, is_local)
232 if self.has_resolvers:
--> 233 return self.resolvers[key]
235 # if we're here that means that we have no locals and we also have
236 # no resolvers
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/collections/__init__.py:1004, in ChainMap.__getitem__(self, key)
1003 pass
-> 1004 return self.__missing__(key)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/collections/__init__.py:996, in ChainMap.__missing__(self, key)
995 def __missing__(self, key):
--> 996 raise KeyError(key)
KeyError: 'continent'
During handling of the above exception, another exception occurred:
KeyError Traceback (most recent call last)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/scope.py:244, in Scope.resolve(self, key, is_local)
240 try:
241 # last ditch effort we look in temporaries
242 # these are created when parsing indexing expressions
243 # e.g., df[df > 0]
--> 244 return self.temps[key]
245 except KeyError as err:
KeyError: 'continent'
The above exception was the direct cause of the following exception:
UndefinedVariableError Traceback (most recent call last)
Cell In[5], line 1
----> 1 africa = world.query('continent == "Africa"')
2 ax = geoplot.cartogram(
3 africa, scale="pop_est", limits=(0.2, 1), edgecolor="None", figsize=(7, 8)
4 )
5 geoplot.polyplot(africa, edgecolor="gray", ax=ax)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/frame.py:4440, in DataFrame.query(self, expr, inplace, **kwargs)
4438 kwargs["level"] = kwargs.pop("level", 0) + 1
4439 kwargs["target"] = None
-> 4440 res = self.eval(expr, **kwargs)
4442 try:
4443 result = self.loc[res]
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/frame.py:4566, in DataFrame.eval(self, expr, inplace, **kwargs)
4563 kwargs["target"] = self
4564 kwargs["resolvers"] = tuple(kwargs.get("resolvers", ())) + resolvers
-> 4566 return _eval(expr, inplace=inplace, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/eval.py:336, in eval(expr, parser, engine, local_dict, global_dict, resolvers, level, target, inplace)
327 # get our (possibly passed-in) scope
328 env = ensure_scope(
329 level + 1,
330 global_dict=global_dict,
(...)
333 target=target,
334 )
--> 336 parsed_expr = Expr(expr, engine=engine, parser=parser, env=env)
338 if engine == "numexpr" and (
339 is_extension_array_dtype(parsed_expr.terms.return_type)
340 or getattr(parsed_expr.terms, "operand_types", None) is not None
(...)
344 )
345 ):
346 warnings.warn(
347 "Engine has switched to 'python' because numexpr does not support "
348 "extension array dtypes. Please set your engine to python manually.",
349 RuntimeWarning,
350 stacklevel=find_stack_level(),
351 )
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:809, in Expr.__init__(self, expr, engine, parser, env, level)
807 self.parser = parser
808 self._visitor = PARSERS[parser](self.env, self.engine, self.parser)
--> 809 self.terms = self.parse()
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:828, in Expr.parse(self)
824 def parse(self):
825 """
826 Parse an expression.
827 """
--> 828 return self._visitor.visit(self.expr)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:415, in BaseExprVisitor.visit(self, node, **kwargs)
413 method = f"visit_{type(node).__name__}"
414 visitor = getattr(self, method)
--> 415 return visitor(node, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:421, in BaseExprVisitor.visit_Module(self, node, **kwargs)
419 raise SyntaxError("only a single expression is allowed")
420 expr = node.body[0]
--> 421 return self.visit(expr, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:415, in BaseExprVisitor.visit(self, node, **kwargs)
413 method = f"visit_{type(node).__name__}"
414 visitor = getattr(self, method)
--> 415 return visitor(node, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:424, in BaseExprVisitor.visit_Expr(self, node, **kwargs)
423 def visit_Expr(self, node, **kwargs):
--> 424 return self.visit(node.value, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:415, in BaseExprVisitor.visit(self, node, **kwargs)
413 method = f"visit_{type(node).__name__}"
414 visitor = getattr(self, method)
--> 415 return visitor(node, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:719, in BaseExprVisitor.visit_Compare(self, node, **kwargs)
717 op = self.translate_In(ops[0])
718 binop = ast.BinOp(op=op, left=node.left, right=comps[0])
--> 719 return self.visit(binop)
721 # recursive case: we have a chained comparison, a CMP b CMP c, etc.
722 left = node.left
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:415, in BaseExprVisitor.visit(self, node, **kwargs)
413 method = f"visit_{type(node).__name__}"
414 visitor = getattr(self, method)
--> 415 return visitor(node, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:535, in BaseExprVisitor.visit_BinOp(self, node, **kwargs)
534 def visit_BinOp(self, node, **kwargs):
--> 535 op, op_class, left, right = self._maybe_transform_eq_ne(node)
536 left, right = self._maybe_downcast_constants(left, right)
537 return self._maybe_evaluate_binop(op, op_class, left, right)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:455, in BaseExprVisitor._maybe_transform_eq_ne(self, node, left, right)
453 def _maybe_transform_eq_ne(self, node, left=None, right=None):
454 if left is None:
--> 455 left = self.visit(node.left, side="left")
456 if right is None:
457 right = self.visit(node.right, side="right")
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:415, in BaseExprVisitor.visit(self, node, **kwargs)
413 method = f"visit_{type(node).__name__}"
414 visitor = getattr(self, method)
--> 415 return visitor(node, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/expr.py:548, in BaseExprVisitor.visit_Name(self, node, **kwargs)
547 def visit_Name(self, node, **kwargs):
--> 548 return self.term_type(node.id, self.env, **kwargs)
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/ops.py:86, in Term.__init__(self, name, env, side, encoding)
84 tname = str(name)
85 self.is_local = tname.startswith(LOCAL_TAG) or tname in DEFAULT_GLOBALS
---> 86 self._value = self._resolve_name()
87 self.encoding = encoding
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/ops.py:110, in Term._resolve_name(self)
105 if local_name in self.env.scope and isinstance(
106 self.env.scope[local_name], type
107 ):
108 is_local = False
--> 110 res = self.env.resolve(local_name, is_local=is_local)
111 self.update(res)
113 if hasattr(res, "ndim") and res.ndim > 2:
File ~/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/pandas/core/computation/scope.py:246, in Scope.resolve(self, key, is_local)
244 return self.temps[key]
245 except KeyError as err:
--> 246 raise UndefinedVariableError(key, is_local) from err
UndefinedVariableError: name 'continent' is not defined
If we have data in the shape of points in space, we may generate a three-dimensional heatmap on it using kdeplot.
[6]:
ax = geoplot.kdeplot(
collisions.head(1000),
clip=boroughs.geometry,
shade=True,
cmap="Reds",
projection=geoplot.crs.AlbersEqualArea(),
)
geoplot.polyplot(boroughs, ax=ax, zorder=1)
/home/docs/checkouts/readthedocs.org/user_builds/geopandas/conda/v0.13.2/lib/python3.11/site-packages/geoplot/geoplot.py:1304: FutureWarning:
`shade` is now deprecated in favor of `fill`; setting `fill=True`.
This will become an error in seaborn v0.14.0; please update your code.
sns.kdeplot(
[6]:
<GeoAxes: >
These are just some of the plots you can make with Geoplot. There are many other possibilities not covered in this brief introduction. For more examples, refer to the Gallery in the Geoplot documentation.