geopandas.GeoSeries.within

GeoSeries.within(other, align=True)

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

An object is said to be within other if at least one of its points is located in the interior and no points are located in the exterior of the other. If either object is empty, this operation returns False.

This is the inverse of contains() in the sense that the expression a.within(b) == b.contains(a) always evaluates to True.

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

../../../_images/binary_op-01.svg
Parameters
otherGeoSeries or geometric object

The GeoSeries (elementwise) or geometric object to test if each geometry is within.

alignbool (default True)

If True, automatically aligns GeoSeries based on their indices. If False, the order of elements is preserved.

Returns
Series (bool)

Notes

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

Examples

>>> from shapely.geometry import Polygon, LineString, Point
>>> s = geopandas.GeoSeries(
...     [
...         Polygon([(0, 0), (2, 2), (0, 2)]),
...         Polygon([(0, 0), (1, 2), (0, 2)]),
...         LineString([(0, 0), (0, 2)]),
...         Point(0, 1),
...     ],
... )
>>> s2 = geopandas.GeoSeries(
...     [
...         Polygon([(0, 0), (1, 1), (0, 1)]),
...         LineString([(0, 0), (0, 2)]),
...         LineString([(0, 0), (0, 1)]),
...         Point(0, 1),
...     ],
...     index=range(1, 5),
... )
>>> s
0    POLYGON ((0.00000 0.00000, 2.00000 2.00000, 0....
1    POLYGON ((0.00000 0.00000, 1.00000 2.00000, 0....
2        LINESTRING (0.00000 0.00000, 0.00000 2.00000)
3                              POINT (0.00000 1.00000)
dtype: geometry
>>> s2
1    POLYGON ((0.00000 0.00000, 1.00000 1.00000, 0....
2        LINESTRING (0.00000 0.00000, 0.00000 2.00000)
3        LINESTRING (0.00000 0.00000, 0.00000 1.00000)
4                              POINT (0.00000 1.00000)
dtype: geometry

We can check if each geometry of GeoSeries is within a single geometry:

../../../_images/binary_op-03.svg
>>> polygon = Polygon([(0, 0), (2, 2), (0, 2)])
>>> s.within(polygon)
0     True
1     True
2    False
3    False
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:

../../../_images/binary_op-02.svg
>>> s2.within(s)
0    False
1    False
2     True
3    False
4    False
dtype: bool
>>> s2.within(s, align=False)
1     True
2    False
3     True
4     True
dtype: bool