Functions¶

Array/Chunked Array functions¶

geoarrow.rust.compute ¶

affine_transform ¶

affine_transform(
    input: ArrowArrayExportable | ArrowStreamExportable,
    transform: AffineTransform,
) -> NativeArray | ChunkedNativeArray

Apply an affine transformation to geometries.

This is intended to be equivalent to shapely.affinity.affine_transform for 2D transforms.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array other: an affine

Returns:

NativeArray | ChunkedNativeArray –

New GeoArrow array or chunked array with the same type as input and with
NativeArray | ChunkedNativeArray –

transformed coordinates.

area ¶

area(
    input: ArrowArrayExportable | ArrowStreamExportable,
    *,
    method: AreaMethod | AreaMethodT = AreaMethod.Euclidean
) -> Array | ChunkedArray

Determine the area of an array of geometries

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array

Other Parameters:

method (AreaMethod | AreaMethodT) –

The method to use for area calculation. One of "Ellipsoidal", "Euclidean", or "Spherical". Refer to the documentation on AreaMethod for more information.

Returns:

Array | ChunkedArray –

Array or chunked array with area values.

center ¶

center(
    input: ArrowArrayExportable | ArrowStreamExportable,
) -> NativeArray | ChunkedNativeArray

Compute the center of geometries

This first computes the axis-aligned bounding rectangle, then takes the center of that box

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array

Returns:

NativeArray | ChunkedNativeArray –

Array or chunked array with center values.

centroid ¶

centroid(
    input: ArrowArrayExportable | ArrowStreamExportable,
) -> NativeArray | ChunkedNativeArray

Calculation of the centroid.

The centroid is the arithmetic mean position of all points in the shape. Informally, it is the point at which a cutout of the shape could be perfectly balanced on the tip of a pin.

The geometric centroid of a convex object always lies in the object. A non-convex object might have a centroid that is outside the object itself.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array

Returns:

NativeArray | ChunkedNativeArray –

Array or chunked array with centroid values.

chaikin_smoothing ¶

chaikin_smoothing(
    input: ArrowArrayExportable | ArrowStreamExportable, n_iterations: int
) -> NativeArray | ChunkedNativeArray

Smoothen LineString, Polygon, MultiLineString and MultiPolygon using Chaikins algorithm.

Chaikins smoothing algorithm

Each iteration of the smoothing doubles the number of vertices of the geometry, so in some cases it may make sense to apply a simplification afterwards to remove insignificant coordinates.

This implementation preserves the start and end vertices of an open linestring and smoothes the corner between start and end of a closed linestring.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array n_iterations: Number of iterations to use for smoothing.

Returns:

NativeArray | ChunkedNativeArray –

Smoothed geometry array or chunked geometry array.

convex_hull ¶

convex_hull(
    input: ArrowArrayExportable | ArrowStreamExportable,
) -> NativeArray | ChunkedNativeArray

Returns the convex hull of a Polygon. The hull is always oriented counter-clockwise.

This implementation uses the QuickHull algorithm, based on Barber, C. Bradford; Dobkin, David P.; Huhdanpaa, Hannu (1 December 1996) Original paper here: www.cs.princeton.edu/~dpd/Papers/BarberDobkinHuhdanpaa.pdf

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array

Returns:

NativeArray | ChunkedNativeArray –

Array with convex hull polygons.

densify ¶

densify(
    input: ArrowArrayExportable, max_distance: float
) -> NativeArray | ChunkedNativeArray

Return a new linear geometry containing both existing and new interpolated coordinates with a maximum distance of max_distance between them.

Note: max_distance must be greater than 0.

Parameters:

input (ArrowArrayExportable) –

input geometry array
max_distance (float) –

maximum distance between coordinates

Returns:

NativeArray | ChunkedNativeArray –

Densified geometry array

envelope ¶

envelope(
    input: ArrowArrayExportable | ArrowStreamExportable,
) -> NativeArray | ChunkedNativeArray

Computes the minimum axis-aligned bounding box that encloses an input geometry

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array

Returns:

NativeArray | ChunkedNativeArray –

Array with axis-aligned bounding boxes.

frechet_distance ¶

frechet_distance(
    input: ArrowArrayExportable | ArrowStreamExportable,
    other: BroadcastGeometry,
) -> Array | ChunkedArray

Determine the similarity between two arrays of LineStrings using the [Frechet distance].

The Fréchet distance is a measure of similarity: it is the greatest distance between any point in A and the closest point in B. The discrete distance is an approximation of this metric: only vertices are considered. The parameter ‘densify’ makes this approximation less coarse by splitting the line segments between vertices before computing the distance.

Fréchet distance sweep continuously along their respective curves and the direction of curves is significant. This makes it a better measure of similarity than Hausdorff distance for curve or surface matching.

This implementation is based on [Computing Discrete Frechet Distance] by T. Eiter and H. Mannila.

[Frechet distance]: en.wikipedia.org/wiki/Fr%C3%A9chet_distance [Computing Discrete Frechet Distance]: www.kr.tuwien.ac.at/staff/eiter/et-archive/cdtr9464.pdf

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array other: the geometry or

Returns:

Array | ChunkedArray –

Array or chunked array with float distance values.

geodesic_perimeter ¶

geodesic_perimeter(
    input: ArrowArrayExportable | ArrowStreamExportable,
) -> Array | ChunkedArray

Determine the perimeter of a geometry on an ellipsoidal model of the earth.

This uses the geodesic measurement methods given by Karney (2013).

For a polygon this returns the sum of the perimeter of the exterior ring and interior rings. To get the perimeter of just the exterior ring of a polygon, do polygon.exterior().geodesic_length().

Units¶

return value: meter

Returns:

Array | ChunkedArray –

Array with output values.

is_empty ¶

is_empty(
    input: ArrowArrayExportable | ArrowStreamExportable,
) -> Array | ChunkedArray

Returns True if a geometry is an empty point, polygon, etc.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array

Returns:

Array | ChunkedArray –

Result array.

length ¶

length(
    input: ArrowArrayExportable | ArrowStreamExportable,
    *,
    method: LengthMethod | LengthMethodT = LengthMethod.Euclidean
) -> Array | ChunkedArray

Calculation of the length of a Line

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array

Other Parameters:

method (LengthMethod | LengthMethodT) –

The method to use for length calculation. One of "Ellipsoidal", "Euclidean", "Haversine", or "Vincenty". Refer to the documentation on LengthMethod for more information. Defaults to LengthMethod.Euclidean.

Returns:

Array | ChunkedArray –

Array or chunked array with length values.

line_interpolate_point ¶

line_interpolate_point(
    input: ArrowArrayExportable | ArrowStreamExportable,
    fraction: (
        float
        | int
        | ArrowArrayExportable
        | ArrowStreamExportable
        | NumpyArrayProtocolf64
    ),
) -> NativeArray | ChunkedNativeArray

Returns a point interpolated at given distance on a line.

This is intended to be equivalent to shapely.line_interpolate_point when normalized=True.

If the given fraction is

less than zero (including negative infinity): returns the starting point
greater than one (including infinity): returns the ending point
If either the fraction is NaN, or any coordinates of the line are not finite, returns Point EMPTY.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array
fraction (float | int | ArrowArrayExportable | ArrowStreamExportable | NumpyArrayProtocolf64) –
the fractional distance along the line. A variety of inputs are accepted:
- A Python float or int
- A numpy ndarray with float64 data type.
- An Arrow array or chunked array with float64 data type.

Returns:

NativeArray | ChunkedNativeArray –

PointArray or ChunkedPointArray with result values

line_locate_point ¶

line_locate_point(
    input: ArrowArrayExportable | ArrowStreamExportable,
    point: GeoInterfaceProtocol | ArrowArrayExportable | ArrowStreamExportable,
) -> Array | ChunkedArray

Returns a fraction of the line's total length representing the location of the closest point on the line to the given point.

This is intended to be equivalent to shapely.line_locate_point when normalized=True.

If the line has zero length the fraction returned is zero.

If either the point's coordinates or any coordinates of the line are not finite, returns NaN.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array
point (GeoInterfaceProtocol | ArrowArrayExportable | ArrowStreamExportable) –
the fractional distance along the line. A variety of inputs are accepted:
- A scalar Geometry
- A NativeArray
- A ChunkedNativeArray
- Any Python class that implements the Geo Interface, such as a shapely Point
- Any GeoArrow array or chunked array of Point type

Returns:

Array | ChunkedArray –

Array or chunked array with float fraction values.

polylabel ¶

polylabel(
    input: ArrowArrayExportable | ArrowStreamExportable, tolerance: float
) -> NativeArray | ChunkedNativeArray

Calculate a Polygon's ideal label position by calculating its pole of inaccessibility.

The pole of inaccessibility is the most distant internal point from the polygon outline (not to be confused with centroid), and is useful for optimal placement of a text label on a polygon.

The calculation uses an iterative grid-based algorithm, ported from the original JavaScript implementation.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array
tolerance (float) –

precision of algorithm. Refer to the original JavaScript documentation for more information

Returns:

NativeArray | ChunkedNativeArray –

PointArray or ChunkedPointArray with result values

rotate ¶

rotate(
    geom: ArrowArrayExportable | ArrowStreamExportable,
    angle: float,
    *,
    origin: RotateOrigin | RotateOriginT | tuple[float, float]
) -> NativeArray | ChunkedNativeArray

scale ¶

scale(
    geom: ArrowArrayExportable | ArrowStreamExportable,
    xfact: float,
    yfact: float,
) -> NativeArray | ChunkedNativeArray

Returns a scaled geometry, scaled by factors along each dimension.

Parameters:

geom (ArrowArrayExportable | ArrowStreamExportable) –

description
xfact (float) –

description
yfact (float) –

description

Returns:

NativeArray | ChunkedNativeArray –

description

signed_area ¶

signed_area(
    input: ArrowArrayExportable | ArrowStreamExportable,
    *,
    method: AreaMethod | AreaMethodT = AreaMethod.Euclidean
) -> Array | ChunkedArray

Signed area of a geometry array

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array or chunked geometry array

Other Parameters:

method (AreaMethod | AreaMethodT) –

The method to use for area calculation. One of "Ellipsoidal", "Euclidean", or "Spherical". Refer to the documentation on AreaMethod for more information.

Returns:

Array | ChunkedArray –

Array or chunked array with area values.

simplify ¶

simplify(
    input: ArrowArrayExportable | ArrowStreamExportable,
    epsilon: float,
    *,
    method: SimplifyMethod | SimplifyMethodT = SimplifyMethod.RDP
) -> NativeArray | ChunkedNativeArray

Simplifies a geometry.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array
epsilon (float) –

tolerance for simplification. An epsilon less than or equal to zero will return an unaltered version of the geometry.

Other Parameters:

method (SimplifyMethod | SimplifyMethodT) –

The method to use for simplification calculation. One of "rdp", "vw", or "vw_preserve". Refer to the documentation on SimplifyMethod for more information. Defaults to SimplifyMethod.RDP.

Returns:

NativeArray | ChunkedNativeArray –

Simplified geometry array.

skew ¶

skew(
    geom: ArrowArrayExportable | ArrowStreamExportable, xs: float, ys: float
) -> NativeArray | ChunkedNativeArray

Skew a geometry from it's bounding box center, using different values for xs and ys to distort the geometry's aspect ratio.

Parameters:

geom (ArrowArrayExportable | ArrowStreamExportable) –

description
xs (float) –

description
ys (float) –

description

Returns:

NativeArray | ChunkedNativeArray –

description

total_bounds ¶

total_bounds(
    input: ArrowArrayExportable | ArrowStreamExportable,
) -> Tuple[float, float, float, float]

Computes the total bounds (extent) of the geometry.

Parameters:

input (ArrowArrayExportable | ArrowStreamExportable) –

input geometry array

Returns:

Tuple[float, float, float, float] –

tuple of (xmin, ymin, xmax, ymax).

translate ¶

translate(
    geom: ArrowArrayExportable | ArrowStreamExportable, xoff: float, yoff: float
) -> NativeArray | ChunkedNativeArray

Returns a scaled geometry, scaled by factors along each dimension.

Parameters:

geom (ArrowArrayExportable | ArrowStreamExportable) –

description
xoff (float) –

description
yoff (float) –

description

Returns:

NativeArray | ChunkedNativeArray –

description

Table functions¶

geoarrow.rust.compute ¶

explode ¶

explode(input: ArrowStreamExportable) -> Table

Explode a table.

This is intended to be equivalent to the explode function in GeoPandas.

Parameters:

input (ArrowStreamExportable) –

input table

Returns:

Table –

A new table with multi-part geometries exploded to separate rows.