"""Set-theoretic operations on geometry objects.""" import warnings import numpy as np from shapely import Geometry, GeometryType, lib from shapely.decorators import ( deprecate_positional, multithreading_enabled, requires_geos, ) __all__ = [ "coverage_union", "coverage_union_all", "difference", "disjoint_subset_union", "disjoint_subset_union_all", "intersection", "intersection_all", "symmetric_difference", "symmetric_difference_all", "unary_union", "union", "union_all", ] # Note: future plan is to change this signature over a few releases: # shapely 2.0: # difference(a, b, grid_size=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'grid_size' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'b' # difference(a, b, *, grid_size=None, **kwargs) @deprecate_positional(["grid_size"], category=DeprecationWarning) @multithreading_enabled def difference(a, b, grid_size=None, **kwargs): """Return the part of geometry A that does not intersect with geometry B. If grid_size is nonzero, input coordinates will be snapped to a precision grid of that size and resulting coordinates will be snapped to that same grid. If 0, this operation will use double precision coordinates. If None, the highest precision of the inputs will be used, which may be previously set using set_precision. Note: returned geometry does not have precision set unless specified previously by set_precision. Parameters ---------- a : Geometry or array_like Geometry or geometries to subtract b from. b : Geometry or array_like Geometry or geometries to subtract from a. grid_size : float, optional Precision grid size; will use the highest precision of the inputs by default. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``grid_size`` is specified as a positional argument. This will need to be specified as a keyword argument in a future release. See Also -------- set_precision Examples -------- >>> import shapely >>> from shapely import LineString >>> line = LineString([(0, 0), (2, 2)]) >>> shapely.difference(line, LineString([(1, 1), (3, 3)])) >>> shapely.difference(line, LineString()) >>> shapely.difference(line, None) is None True >>> box1 = shapely.box(0, 0, 2, 2) >>> box2 = shapely.box(1, 1, 3, 3) >>> shapely.difference(box1, box2).normalize() >>> box1 = shapely.box(0.1, 0.2, 2.1, 2.1) >>> shapely.difference(box1, box2, grid_size=1) """ if grid_size is not None: if not np.isscalar(grid_size): raise ValueError("grid_size parameter only accepts scalar values") return lib.difference_prec(a, b, grid_size, **kwargs) return lib.difference(a, b, **kwargs) # Note: future plan is to change this signature over a few releases: # shapely 2.0: # intersection(a, b, grid_size=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'grid_size' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'b' # intersection(a, b, *, grid_size=None, **kwargs) @deprecate_positional(["grid_size"], category=DeprecationWarning) @multithreading_enabled def intersection(a, b, grid_size=None, **kwargs): """Return the geometry that is shared between input geometries. If grid_size is nonzero, input coordinates will be snapped to a precision grid of that size and resulting coordinates will be snapped to that same grid. If 0, this operation will use double precision coordinates. If None, the highest precision of the inputs will be used, which may be previously set using set_precision. Note: returned geometry does not have precision set unless specified previously by set_precision. Parameters ---------- a, b : Geometry or array_like Geometry or geometries to intersect with. grid_size : float, optional Precision grid size; will use the highest precision of the inputs by default. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``grid_size`` is specified as a positional argument. This will need to be specified as a keyword argument in a future release. See Also -------- intersection_all set_precision Examples -------- >>> import shapely >>> from shapely import LineString >>> line = LineString([(0, 0), (2, 2)]) >>> shapely.intersection(line, LineString([(1, 1), (3, 3)])) >>> box1 = shapely.box(0, 0, 2, 2) >>> box2 = shapely.box(1, 1, 3, 3) >>> shapely.intersection(box1, box2).normalize() >>> box1 = shapely.box(0.1, 0.2, 2.1, 2.1) >>> shapely.intersection(box1, box2, grid_size=1) """ if grid_size is not None: if not np.isscalar(grid_size): raise ValueError("grid_size parameter only accepts scalar values") return lib.intersection_prec(a, b, grid_size, **kwargs) return lib.intersection(a, b, **kwargs) # Note: future plan is to change this signature over a few releases: # shapely 2.0: # intersection_all(geometries, axis=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'axis' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'geometries' # intersection_all(geometries, *, axis=None, **kwargs) @deprecate_positional(["axis"], category=DeprecationWarning) @multithreading_enabled def intersection_all(geometries, axis=None, **kwargs): """Return the intersection of multiple geometries. This function ignores None values when other Geometry elements are present. If all elements of the given axis are None, an empty GeometryCollection is returned. Parameters ---------- geometries : array_like Geometries to calculate the intersection of. axis : int, optional Axis along which the operation is performed. The default (None) performs the operation over all axes, returning a scalar value. Axis may be negative, in which case it counts from the last to the first axis. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``axis`` is specified as a positional argument. This will need to be specified as a keyword argument in a future release. See Also -------- intersection Examples -------- >>> import shapely >>> from shapely import LineString >>> line1 = LineString([(0, 0), (2, 2)]) >>> line2 = LineString([(1, 1), (3, 3)]) >>> shapely.intersection_all([line1, line2]) >>> shapely.intersection_all([[line1, line2, None]], axis=1).tolist() [] >>> shapely.intersection_all([line1, None]) """ geometries = np.asarray(geometries) if axis is None: geometries = geometries.ravel() else: geometries = np.rollaxis(geometries, axis=axis, start=geometries.ndim) return lib.intersection_all(geometries, **kwargs) # Note: future plan is to change this signature over a few releases: # shapely 2.0: # symmetric_difference(a, b, grid_size=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'grid_size' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'b' # symmetric_difference(a, b, *, grid_size=None, **kwargs) @deprecate_positional(["grid_size"], category=DeprecationWarning) @multithreading_enabled def symmetric_difference(a, b, grid_size=None, **kwargs): """Return the geometry with the portions of input geometries that do not intersect. If grid_size is nonzero, input coordinates will be snapped to a precision grid of that size and resulting coordinates will be snapped to that same grid. If 0, this operation will use double precision coordinates. If None, the highest precision of the inputs will be used, which may be previously set using set_precision. Note: returned geometry does not have precision set unless specified previously by set_precision. Parameters ---------- a, b : Geometry or array_like Geometry or geometries to evaluate symmetric difference with. grid_size : float, optional Precision grid size; will use the highest precision of the inputs by default. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``grid_size`` is specified as a positional argument. This will need to be specified as a keyword argument in a future release. See Also -------- symmetric_difference_all set_precision Examples -------- >>> import shapely >>> from shapely import LineString >>> line = LineString([(0, 0), (2, 2)]) >>> shapely.symmetric_difference(line, LineString([(1, 1), (3, 3)])) >>> box1 = shapely.box(0, 0, 2, 2) >>> box2 = shapely.box(1, 1, 3, 3) >>> shapely.symmetric_difference(box1, box2).normalize() >>> box1 = shapely.box(0.1, 0.2, 2.1, 2.1) >>> shapely.symmetric_difference(box1, box2, grid_size=1) """ if grid_size is not None: if not np.isscalar(grid_size): raise ValueError("grid_size parameter only accepts scalar values") return lib.symmetric_difference_prec(a, b, grid_size, **kwargs) return lib.symmetric_difference(a, b, **kwargs) # Note: future plan is to change this signature over a few releases: # shapely 2.0: # symmetric_difference_all(geometries, axis=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'axis' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'geometries' # symmetric_difference_all(geometries, *, axis=None, **kwargs) @deprecate_positional(["axis"], category=DeprecationWarning) @multithreading_enabled def symmetric_difference_all(geometries, axis=None, **kwargs): """Return the symmetric difference of multiple geometries. This function ignores None values when other Geometry elements are present. If all elements of the given axis are None an empty GeometryCollection is returned. .. deprecated:: 2.1.0 This function behaves incorrectly and will be removed in a future version. See https://github.com/shapely/shapely/issues/2027 for more details. Parameters ---------- geometries : array_like Geometries to calculate the combined symmetric difference of. axis : int, optional Axis along which the operation is performed. The default (None) performs the operation over all axes, returning a scalar value. Axis may be negative, in which case it counts from the last to the first axis. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``axis`` is specified as a positional argument. This will need to be specified as a keyword argument in a future release. See Also -------- symmetric_difference Examples -------- >>> import shapely >>> from shapely import LineString >>> line1 = LineString([(0, 0), (2, 2)]) >>> line2 = LineString([(1, 1), (3, 3)]) >>> shapely.symmetric_difference_all([line1, line2]) >>> shapely.symmetric_difference_all([[line1, line2, None]], axis=1).tolist() [] >>> shapely.symmetric_difference_all([line1, None]) >>> shapely.symmetric_difference_all([None, None]) """ warnings.warn( "The symmetric_difference_all function behaves incorrectly and will be " "removed in a future version. " "See https://github.com/shapely/shapely/issues/2027 for more details.", DeprecationWarning, stacklevel=2, ) geometries = np.asarray(geometries) if axis is None: geometries = geometries.ravel() else: geometries = np.rollaxis(geometries, axis=axis, start=geometries.ndim) return lib.symmetric_difference_all(geometries, **kwargs) # Note: future plan is to change this signature over a few releases: # shapely 2.0: # union(a, b, grid_size=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'grid_size' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'b' # union(a, b, *, grid_size=None, **kwargs) @deprecate_positional(["grid_size"], category=DeprecationWarning) @multithreading_enabled def union(a, b, grid_size=None, **kwargs): """Merge geometries into one. If grid_size is nonzero, input coordinates will be snapped to a precision grid of that size and resulting coordinates will be snapped to that same grid. If 0, this operation will use double precision coordinates. If None, the highest precision of the inputs will be used, which may be previously set using set_precision. Note: returned geometry does not have precision set unless specified previously by set_precision. Parameters ---------- a, b : Geometry or array_like Geometry or geometries to merge (union). grid_size : float, optional Precision grid size; will use the highest precision of the inputs by default. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``grid_size`` is specified as a positional argument. This will need to be specified as a keyword argument in a future release. See Also -------- union_all set_precision Examples -------- >>> import shapely >>> from shapely import LineString >>> line = LineString([(0, 0), (2, 2)]) >>> shapely.union(line, LineString([(2, 2), (3, 3)])) >>> shapely.union(line, None) is None True >>> box1 = shapely.box(0, 0, 2, 2) >>> box2 = shapely.box(1, 1, 3, 3) >>> shapely.union(box1, box2).normalize() >>> box1 = shapely.box(0.1, 0.2, 2.1, 2.1) >>> shapely.union(box1, box2, grid_size=1) """ if grid_size is not None: if not np.isscalar(grid_size): raise ValueError("grid_size parameter only accepts scalar values") return lib.union_prec(a, b, grid_size, **kwargs) return lib.union(a, b, **kwargs) # Note: future plan is to change this signature over a few releases: # shapely 2.0: # union_all(geometries, grid_size=None, axis=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'grid_size' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'geometries' # union_all(geometries, *, grid_size=None, axis=None, **kwargs) @deprecate_positional(["grid_size", "axis"], category=DeprecationWarning) @multithreading_enabled def union_all(geometries, grid_size=None, axis=None, **kwargs): """Return the union of multiple geometries. This function ignores None values when other Geometry elements are present. If all elements of the given axis are None an empty GeometryCollection is returned. If grid_size is nonzero, input coordinates will be snapped to a precision grid of that size and resulting coordinates will be snapped to that same grid. If 0, this operation will use double precision coordinates. If None, the highest precision of the inputs will be used, which may be previously set using set_precision. Note: returned geometry does not have precision set unless specified previously by set_precision. `unary_union` is an alias of `union_all`. Parameters ---------- geometries : array_like Geometries to merge/union. grid_size : float, optional Precision grid size; will use the highest precision of the inputs by default. axis : int, optional Axis along which the operation is performed. The default (None) performs the operation over all axes, returning a scalar value. Axis may be negative, in which case it counts from the last to the first axis. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``grid_size`` or ``axis`` are specified as positional arguments. In a future release, these will need to be specified as keyword arguments. See Also -------- union set_precision Examples -------- >>> import shapely >>> from shapely import LineString, Point >>> line1 = LineString([(0, 0), (2, 2)]) >>> line2 = LineString([(2, 2), (3, 3)]) >>> shapely.union_all([line1, line2]) >>> shapely.union_all([[line1, line2, None]], axis=1).tolist() [] >>> box1 = shapely.box(0, 0, 2, 2) >>> box2 = shapely.box(1, 1, 3, 3) >>> shapely.union_all([box1, box2]).normalize() >>> box1 = shapely.box(0.1, 0.2, 2.1, 2.1) >>> shapely.union_all([box1, box2], grid_size=1) >>> shapely.union_all([None, Point(0, 1)]) >>> shapely.union_all([None, None]) >>> shapely.union_all([]) """ # for union_all, GEOS provides an efficient route through first creating # GeometryCollections # first roll the aggregation axis backwards geometries = np.asarray(geometries) if axis is None: geometries = geometries.ravel() else: geometries = np.rollaxis(geometries, axis=axis, start=geometries.ndim) # create_collection acts on the inner axis collections = lib.create_collection( geometries, np.intc(GeometryType.GEOMETRYCOLLECTION) ) if grid_size is not None: if not np.isscalar(grid_size): raise ValueError("grid_size parameter only accepts scalar values") return lib.unary_union_prec(collections, grid_size, **kwargs) return lib.unary_union(collections, **kwargs) unary_union = union_all @multithreading_enabled def coverage_union(a, b, **kwargs): """Merge multiple polygons into one. This is an optimized version of union which assumes the polygons to be non-overlapping. Parameters ---------- a, b : Geometry or array_like Geometry or geometries to merge (union). **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. See Also -------- coverage_union_all Examples -------- >>> import shapely >>> from shapely import Polygon >>> polygon_1 = Polygon([(0, 0), (0, 1), (1, 1), (1, 0), (0, 0)]) >>> polygon_2 = Polygon([(1, 0), (1, 1), (2, 1), (2, 0), (1, 0)]) >>> shapely.coverage_union(polygon_1, polygon_2).normalize() Union with None returns same polygon >>> shapely.coverage_union(polygon_1, None).normalize() """ return coverage_union_all([a, b], **kwargs) # Note: future plan is to change this signature over a few releases: # shapely 2.0: # coverage_union_all(geometries, axis=None, **kwargs) # shapely 2.1: shows deprecation warning about positional 'axis' arg # same signature as 2.0 # shapely 2.2(?): enforce keyword-only arguments after 'geometries' # coverage_union_all(geometries, *, axis=None, **kwargs) @deprecate_positional(["axis"], category=DeprecationWarning) @multithreading_enabled def coverage_union_all(geometries, axis=None, **kwargs): """Return the union of multiple polygons of a geometry collection. This is an optimized version of union which assumes the polygons to be non-overlapping. This function ignores None values when other Geometry elements are present. If all elements of the given axis are None, an empty GeometryCollection is returned (before GEOS 3.12 this was an empty MultiPolygon). Parameters ---------- geometries : array_like Geometries to merge/union. axis : int, optional Axis along which the operation is performed. The default (None) performs the operation over all axes, returning a scalar value. Axis may be negative, in which case it counts from the last to the first axis. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. Notes ----- .. deprecated:: 2.1.0 A deprecation warning is shown if ``axis`` is specified as a positional argument. This will need to be specified as a keyword argument in a future release. See Also -------- coverage_union Examples -------- >>> import shapely >>> from shapely import Polygon >>> polygon_1 = Polygon([(0, 0), (0, 1), (1, 1), (1, 0), (0, 0)]) >>> polygon_2 = Polygon([(1, 0), (1, 1), (2, 1), (2, 0), (1, 0)]) >>> shapely.coverage_union_all([polygon_1, polygon_2]).normalize() >>> shapely.coverage_union_all([polygon_1, None]).normalize() >>> shapely.coverage_union_all([None, None]).normalize() """ # coverage union in GEOS works over GeometryCollections # first roll the aggregation axis backwards geometries = np.asarray(geometries) if axis is None: geometries = geometries.ravel() else: geometries = np.rollaxis( np.asarray(geometries), axis=axis, start=geometries.ndim ) # create_collection acts on the inner axis collections = lib.create_collection( geometries, np.intc(GeometryType.GEOMETRYCOLLECTION) ) return lib.coverage_union(collections, **kwargs) @requires_geos("3.12.0") @multithreading_enabled def disjoint_subset_union(a, b, **kwargs): """Merge multiple polygons into one using algorithm optimised for subsets. This is an optimized version of union which assumes inputs can be divided into subsets that do not intersect. If there is only one such subset, performance can be expected to be worse than :func:`union`. As such, it is recommeded to use ``disjoint_subset_union`` with GeometryCollections rather than individual geometries. .. versionadded:: 2.1.0 Parameters ---------- a, b : Geometry or array_like Geometry or geometries to merge (union). **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. See Also -------- union coverage_union disjoint_subset_union_all Examples -------- >>> import shapely >>> from shapely import Polygon >>> polygon_1 = Polygon([(0, 0), (0, 1), (1, 1), (1, 0), (0, 0)]) >>> polygon_2 = Polygon([(1, 0), (1, 1), (2, 1), (2, 0), (1, 0)]) >>> shapely.disjoint_subset_union(polygon_1, polygon_2).normalize() Union with None returns same polygon: >>> shapely.disjoint_subset_union(polygon_1, None).normalize() """ if (isinstance(a, Geometry) or a is None) and ( isinstance(b, Geometry) or b is None ): pass elif isinstance(a, Geometry) or a is None: a = np.full_like(b, a) elif isinstance(b, Geometry) or b is None: b = np.full_like(a, b) elif len(a) != len(b): raise ValueError("Arrays a and b must have the same length") return disjoint_subset_union_all([a, b], axis=0, **kwargs) @requires_geos("3.12.0") @multithreading_enabled def disjoint_subset_union_all(geometries, *, axis=None, **kwargs): """Return the union of multiple polygons. This is an optimized version of union which assumes inputs can be divided into subsets that do not intersect. If there is only one such subset, performance can be expected to be worse than :func:`union_all`. This function ignores None values when other Geometry elements are present. If all elements of the given axis are None, an empty GeometryCollection is returned. .. versionadded:: 2.1.0 Parameters ---------- geometries : array_like Geometries to union. axis : int, optional Axis along which the operation is performed. The default (None) performs the operation over all axes, returning a scalar value. Axis may be negative, in which case it counts from the last to the first axis. **kwargs See :ref:`NumPy ufunc docs ` for other keyword arguments. See Also -------- coverage_union_all union_all disjoint_subset_union Examples -------- >>> import shapely >>> from shapely import Polygon >>> polygon_1 = Polygon([(0, 0), (0, 1), (1, 1), (1, 0), (0, 0)]) >>> polygon_2 = Polygon([(1, 0), (1, 1), (2, 1), (2, 0), (1, 0)]) >>> shapely.disjoint_subset_union_all([polygon_1, polygon_2]).normalize() >>> shapely.disjoint_subset_union_all([polygon_1, None]).normalize() >>> shapely.disjoint_subset_union_all([None, None]).normalize() """ geometries = np.asarray(geometries) if axis is None: geometries = geometries.ravel() else: geometries = np.rollaxis( np.asarray(geometries), axis=axis, start=geometries.ndim ) # create_collection acts on the inner axis collections = lib.create_collection( geometries, np.intc(GeometryType.GEOMETRYCOLLECTION) ) return lib.disjoint_subset_union(collections, **kwargs)