geopandas.GeoSeries.touches#

GeoSeries.touches(other, align=True)[source]#

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

An object is said to touch other if it has at least one point in common with other and its interior does not intersect with any part of the other. Overlapping features therefore do not touch.

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 is touched.

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 touches any element of the other one.

Examples

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

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

../../../_images/binary_op-03.svg
>>> line = LineString([(0, 0), (-1, -2)])
>>> s.touches(line)
0    True
1    True
2    True
3    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:

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