geopandas.GeoSeries.dwithin

GeoSeries.dwithin(other, distance, align=None)

Returns a Series of dtype('bool') with value True for each aligned geometry that is within a set distance from other.

The operation works on a 1-to-1 row-wise manner:

Parameters:

otherGeoSeries or geometric object

The GeoSeries (elementwise) or geometric object to test for equality.

distancefloat, np.array, pd.Series

Distance(s) to test if each geometry is within. A scalar distance will be applied to all geometries. An array or Series will be applied elementwise. If np.array or pd.Series are used then it must have same length as the GeoSeries.

alignbool | None (default None)

If True, automatically aligns GeoSeries based on their indices. If False, the order of elements is preserved. None defaults to True.

Returns:

Series (bool)

See also

GeoSeries.within

Notes

This method works in a row-wise manner. It does not check if an element of one GeoSeries is within the set distance of any element of the other one.

Examples

>>> from shapely.geometry import Polygon, LineString, Point
>>> s = geopandas.GeoSeries(
...     [
...         Polygon([(0, 0), (1, 1), (0, 1)]),
...         LineString([(0, 0), (0, 2)]),
...         LineString([(0, 0), (0, 1)]),
...         Point(0, 1),
...     ],
...     index=range(0, 4),
... )
>>> s2 = geopandas.GeoSeries(
...     [
...         Polygon([(1, 0), (4, 2), (2, 2)]),
...         Polygon([(2, 0), (3, 2), (2, 2)]),
...         LineString([(2, 0), (2, 2)]),
...         Point(1, 1),
...     ],
...     index=range(1, 5),
... )

>>> s
0    POLYGON ((0 0, 1 1, 0 1, 0 0))
1             LINESTRING (0 0, 0 2)
2             LINESTRING (0 0, 0 1)
3                       POINT (0 1)
dtype: geometry

>>> s2
1    POLYGON ((1 0, 4 2, 2 2, 1 0))
2    POLYGON ((2 0, 3 2, 2 2, 2 0))
3             LINESTRING (2 0, 2 2)
4                       POINT (1 1)
dtype: geometry

We can check if each geometry of GeoSeries contains a single geometry:

>>> point = Point(0, 1)
>>> s2.dwithin(point, 1.8)
1     True
2    False
3    False
4     True
dtype: bool

We can also check two GeoSeries against each other, row by row. The GeoSeries above have different indices. We can either align both GeoSeries based on index values and compare elements with the same index using align=True or ignore index and compare elements based on their matching order using align=False:

>>> s.dwithin(s2, distance=1, align=True)
0    False
1     True
2    False
3    False
4    False
dtype: bool

>>> s.dwithin(s2, distance=1, align=False)
0     True
1    False
2    False
3     True
dtype: bool