Geometry

wrap_to_180(lon)

Wrap angle(s) to the range [-180, 180) degrees.

Parameters:

lon (float or array-like) – Angle(s) in degrees.

Returns:

Angle(s) wrapped to [-180, 180).

Return type:

numpy.ndarray or float

wrap_to_360(angle)

Wrap angle(s) to the range [0, 360) degrees.

Parameters:

angle (float or array-like) – Angle(s) in degrees.

Returns:

Angle(s) wrapped to [0, 360).

Return type:

numpy.ndarray

calculate_geographic_mean(geometry)

Calculate the geographic mean of coordinates from a Shapely geometry or a list of Shapely geometries using pymap3d.lox.meanm.

Parameters:

geometry (LineString, Polygon, Point, or list) – A single Shapely geometry or a list of Shapely geometries.

Returns:

Geographic mean as a Shapely Point.

Return type:

Point

get_utm_crs(lon, lat)

Determine the UTM CRS for a given WGS84 coordinate using the area of interest (AOI).

Parameters:

• lon (float) – Longitude in decimal degrees (WGS84).

• lat (float) – Latitude in decimal degrees (WGS84).

Returns:

The appropriate UTM CRS for the coordinate.

Return type:

CRS

get_utm_transforms(geometry)

Get the UTM CRS and transformation functions to/from WGS84 for a Shapely geometry or a list of geometries.

Parameters:

geometry (BaseGeometry or list of BaseGeometry) – A single Shapely geometry object or a list of geometries.

Returns:

Transformation functions:

• wgs84_to_utm: Function to transform coordinates from WGS84 to UTM.

• utm_to_wgs84: Function to transform coordinates from UTM to WGS84.

Return type:

Tuple[Callable, Callable]

Raises:

ValueError – If the geometry is invalid, empty, or has no valid centroid.

haversine(lat1, lon1, lat2, lon2, radius=6371000.0)

Calculate the haversine distance between two points on the Earth’s surface.

Parameters:

• lat1 (float) – Latitude of the first point in decimal degrees.

• lon1 (float) – Longitude of the first point in decimal degrees.

• lat2 (float) – Latitude of the second point in decimal degrees.

• lon2 (float) – Longitude of the second point in decimal degrees.

• radius (float) – Radius of the Earth in meters (default: 6371e3 for meters).

Returns:

Distance between the two points in the same unit as the radius.

Return type:

float

random_points_in_polygon(polygon, k)

Generate k points chosen uniformly at random inside a polygon.

Uses Delaunay triangulation with area-weighted sampling to ensure uniform distribution across the polygon’s interior.

Parameters:

• polygon (Polygon) – A Shapely Polygon to sample points from.

• k (int) – Number of random points to generate.

Returns:

List of k Shapely Point objects inside the polygon.

Return type:

list[Point]

minimum_rotated_rectangle(polygon)

Calculate the minimum rotated rectangle of a polygon in WGS84 coordinates.

Parameters:

polygon (Polygon) – Input polygon in WGS84 coordinates. Must be valid.

Returns:

A tuple containing:

• lat0 (float): Latitude of the rectangle’s centroid.

• lon0 (float): Longitude of the rectangle’s centroid.

• azimuth (float): Azimuth of the rectangle in degrees, wrapped to [-180, 180].

• length (float): Length of the rectangle’s longer side (meters).

• width (float): Width of the rectangle’s shorter side (meters).

• mrr_wgs84 (Polygon): Minimum rotated rectangle in WGS84 coordinates.

• hull_wgs84 (Polygon): Convex hull of the polygon in WGS84 coordinates.

Return type:

tuple

Raises:

ValueError – If the input polygon is invalid or processing fails.

Notes

• The input polygon is transformed to UTM for accurate geometry calculations.

• Returns both the rectangle and the convex hull in WGS84 coordinates.

rotated_rectangle(polygon, azimuth)

Compute a rotated bounding rectangle around a Shapely polygon in WGS84 coordinates at a specified azimuth.

Parameters:

• polygon (Polygon) – Input polygon in WGS84 coordinates. Must be valid.

• azimuth (float) – Desired azimuth for the bounding rectangle in degrees. Will be wrapped to [-180, 180].

Returns:

The rotated bounding rectangle in WGS84 coordinates.

Return type:

Polygon

Raises:

ValueError – If the input polygon is invalid or if an error occurs during processing.

Notes

• The input polygon is transformed to UTM for accurate geometry calculations.

• The bounding rectangle is rotated to align with the specified azimuth.

• The result is returned in WGS84 coordinates.

translate_polygon(polygon, distance, azimuth)

Translate a Shapely polygon by a specified distance in a given rotational direction.

Parameters:

• polygon (Polygon) – The input Shapely polygon to be translated

• distance (float) – Distance to translate the polygon (in the same units as the polygon’s coordinates).

• azimuth (float) – Angle of translation in degrees, measured clockwise from north.

Returns:

The translated Shapely polygon.

Return type:

Polygon

buffer_polygon_along_azimuth(polygon, along_track_distance, across_track_distance, azimuth)

Translate a Shapely polygon in both a specified direction and its opposite, then compute the convex hull of the union of the two translated polygons.

Parameters:

• polygon (Polygon) – The input Shapely polygon to be buffered in WGS84 coordinates. Must be valid.

• distance (ureg.Quantity) – Distance to translate the polygon. Must be a positive length Quantity.

• azimuth (float) – Angle of translation in degrees, measured clockwise from north.

• along_track_distance (float)

• across_track_distance (float)

Returns:

The convex hull of the union of the two translated polygons in WGS84 coordinates.

Return type:

Polygon

Raises:

ValueError – If the input polygon is invalid or if distance is not a valid length.

Notes

• The input polygon is transformed to UTM for accurate geometry calculations.

• The resulting convex hull is returned in WGS84 coordinates.

process_linestring(linestring)

Process a LineString containing WGS84 coordinates to compute latitudes, longitudes, azimuths, and cumulative along-track distances.

Parameters:

linestring (LineString) – A shapely LineString containing WGS84 coordinates.

Returns:

A tuple containing:

• numpy.ndarray: Latitudes of the track points.

• numpy.ndarray: Longitudes of the track points.

• numpy.ndarray: Azimuths between consecutive points.

• numpy.ndarray: Cumulative along-track distances in meters.

Return type:

tuple