Coordinate operations¶

pygeos.coordinates.apply(geometry, transformation, include_z=False)¶

Returns a copy of a geometry array with a function applied to its coordinates.

With the default of include_z=False, all returned geometries will be two-dimensional; the third dimension will be discarded, if present. When specifying include_z=True, the returned geometries preserve the dimensionality of the respective input geometries.

Parameters

geometryGeometry or array_like
transformationfunction: A function that transforms a (N, 2) or (N, 3) ndarray of float64 to another (N, 2) or (N, 3) ndarray of float64.
include_zbool, default False: Whether to include the third dimension in the coordinates array that is passed to the transformation function. If True, and a geometry has no third dimension, the z-coordinates passed to the function will be NaN.

Examples

>>> apply(Geometry("POINT (0 0)"), lambda x: x + 1)
<pygeos.Geometry POINT (1 1)>
>>> apply(Geometry("LINESTRING (2 2, 4 4)"), lambda x: x * [2, 3])
<pygeos.Geometry LINESTRING (4 6, 8 12)>
>>> apply(None, lambda x: x) is None
True
>>> apply([Geometry("POINT (0 0)"), None], lambda x: x).tolist()
[<pygeos.Geometry POINT (0 0)>, None]

By default, the third dimension is ignored:

>>> apply(Geometry("POINT Z (0 0 0)"), lambda x: x + 1)
<pygeos.Geometry POINT (1 1)>
>>> apply(Geometry("POINT Z (0 0 0)"), lambda x: x + 1, include_z=True)
<pygeos.Geometry POINT Z (1 1 1)>

pygeos.coordinates.count_coordinates(geometry)¶

Counts the number of coordinate pairs in a geometry array.

Parameters

geometryGeometry or array_like

Examples

>>> count_coordinates(Geometry("POINT (0 0)"))
1
>>> count_coordinates(Geometry("LINESTRING (2 2, 4 4)"))
2
>>> count_coordinates(None)
0
>>> count_coordinates([Geometry("POINT (0 0)"), None])
1

pygeos.coordinates.get_coordinates(geometry, include_z=False)¶

Gets coordinates from a geometry array as an array of floats.

The shape of the returned array is (N, 2), with N being the number of coordinate pairs. With the default of include_z=False, three-dimensional data is ignored. When specifying include_z=True, the shape of the returned array is (N, 3).

Parameters

geometryGeometry or array_like
include_zbool, default False: Whether to include the third dimension in the output. If True, and a geometry has no third dimension, the z-coordinates will be NaN.

Examples

>>> get_coordinates(Geometry("POINT (0 0)")).tolist()
[[0.0, 0.0]]
>>> get_coordinates(Geometry("LINESTRING (2 2, 4 4)")).tolist()
[[2.0, 2.0], [4.0, 4.0]]
>>> get_coordinates(None)
array([], shape=(0, 2), dtype=float64)

By default the third dimension is ignored:

>>> get_coordinates(Geometry("POINT Z (0 0 0)")).tolist()
[[0.0, 0.0]]
>>> get_coordinates(Geometry("POINT Z (0 0 0)"), include_z=True).tolist()
[[0.0, 0.0, 0.0]]

pygeos.coordinates.set_coordinates(geometry, coordinates)¶

Returns a copy of a geometry array with different coordinates.

If the coordinates array has shape (N, 2), all returned geometries will be two-dimensional, and the third dimension will be discarded, if present. If the coordinates array has shape (N, 3), the returned geometries preserve the dimensionality of the input geometries.

Parameters

geometryGeometry or array_like
coordinates: array_like

Examples

>>> set_coordinates(Geometry("POINT (0 0)"), [[1, 1]])
<pygeos.Geometry POINT (1 1)>
>>> set_coordinates([Geometry("POINT (0 0)"), Geometry("LINESTRING (0 0, 0 0)")], [[1, 2], [3, 4], [5, 6]]).tolist()
[<pygeos.Geometry POINT (1 2)>, <pygeos.Geometry LINESTRING (3 4, 5 6)>]
>>> set_coordinates([None, Geometry("POINT (0 0)")], [[1, 2]]).tolist()
[None, <pygeos.Geometry POINT (1 2)>]

Third dimension of input geometry is discarded if coordinates array does not include one:

>>> set_coordinates(Geometry("POINT Z (0 0 0)"), [[1, 1]])
<pygeos.Geometry POINT (1 1)>
>>> set_coordinates(Geometry("POINT Z (0 0 0)"), [[1, 1, 1]])
<pygeos.Geometry POINT Z (1 1 1)>