libpysal API reference

Spatial Graph

Modern implementation of spatial graphs encoding spatial weights matrices.

libpysal.graph.Graph(adjacency[, ...])	Graph class encoding spatial weights matrices
libpysal.graph.GraphSummary(graph[, asymmetries])	Graph Summary
libpysal.graph.read_parquet(path, **kwargs)	Read Graph from a Apache Parquet
libpysal.graph.read_gal(path)	Read Graph from a GAL file
libpysal.graph.read_gwt(path)	Read Graph from a GWT file

Spatial Weights

Legacy implementation of spatial weights matrices.

libpysal.weights.W(neighbors[, weights, ...])

Spatial weights class.

Distance Weights

libpysal.weights.DistanceBand(data, threshold)	Spatial weights based on distance band.
libpysal.weights.Kernel(data[, bandwidth, ...])	Spatial weights based on kernel functions.
libpysal.weights.KNN(data[, k, p, ids, ...])	Creates nearest neighbor weights matrix based on k nearest neighbors.
libpysal.weights.Gabriel(coordinates, **kwargs)	Constructs the Gabriel graph of a set of points.
libpysal.weights.Delaunay(coordinates, **kwargs)	Constructor of the Delaunay graph of a set of input points.
libpysal.weights.Relative_Neighborhood(...)	Constructs the Relative Neighborhood graph from a set of points.

Contiguity Weights

libpysal.weights.Queen(polygons, **kw)	Construct a weights object from a collection of pysal polygons that share at least one vertex.
libpysal.weights.Rook(polygons, **kw)	Construct a weights object from a collection of pysal polygons that share at least one edge.
libpysal.weights.Voronoi(points[, ...])	Voronoi weights for a 2-d point set
libpysal.weights.W(neighbors[, weights, ...])	Spatial weights class.

spint Weights

libpysal.weights.WSP(sparse[, id_order, index])	Thin W class for spreg.
libpysal.weights.netW(link_list[, share, ...])	Create a network-contiguity based weight object based on different nodal relationships encoded in a network.
libpysal.weights.mat2L(edge_matrix)	Convert a matrix denoting network connectivity (edges or flows) to a list denoting edges
libpysal.weights.ODW(Wo, Wd[, transform, ...])	Constructs an o*d by o*d origin-destination style spatial weight for o*d flows using standard spatial weights on o origins and d destinations.
libpysal.weights.vecW(origin_x, origin_y, ...)	Distance-based spatial weight for vectors that is computed using a 4-dimensional distance between the origin x,y-coordinates and the destination x,y-coordinates

Weights tools to interface with rasters

libpysal.weights.da2W(da[, criterion, ...])	Create a W object from xarray.DataArray with an additional attribute index containing coordinate values of the raster in the form of Pandas.Index/MultiIndex.
libpysal.weights.da2WSP(da[, criterion, ...])	Create a WSP object from xarray.DataArray with an additional attribute index containing coordinate values of the raster in the form of Pandas.Index/MultiIndex.
libpysal.weights.w2da(data, w[, attrs, coords])	Creates xarray.DataArray object from passed data aligned with W object.
libpysal.weights.wsp2da(data, wsp[, attrs, ...])	Creates xarray.DataArray object from passed data aligned with WSP object.
libpysal.weights.testDataArray([shape, ...])	Creates 2 or 3 dimensional test xarray.DataArray object

Weights Util Classes and Functions

libpysal.weights.block_weights(regimes[, ...])	Construct spatial weights for regime neighbors.
libpysal.weights.lat2W([nrows, ncols, rook, ...])	Create a W object for a regular lattice.
libpysal.weights.comb(items[, n])	Combinations of size n taken from items
libpysal.weights.order(w[, kmax])	Determine the non-redundant order of contiguity up to a specific order.
libpysal.weights.higher_order(w[, k])	Contiguity weights object of order k.
libpysal.weights.shimbel(w)	Find the Shimbel matrix for first order contiguity matrix.
libpysal.weights.remap_ids(w, old2new[, ...])	Remaps the IDs in a spatial weights object.
libpysal.weights.full2W(m[, ids])	Create a PySAL W object from a full array.
libpysal.weights.full(w)	Generate a full numpy array.
libpysal.weights.WSP2W(wsp, **kwargs)	Convert a pysal WSP object (thin weights matrix) to a pysal W object.
libpysal.weights.get_ids(in_shps, idVariable)	Gets the IDs from the DBF file that moves with a given shape file or a geopandas.GeoDataFrame.
libpysal.weights.get_points_array_from_shapefile(...)	Gets a data array of x and y coordinates from a given shapefile.
libpysal.weights.fill_diagonal(w[, val, wsp])	Returns a new weights object with values inserted along the main diagonal.

Weights user Classes and Functions

libpysal.weights.min_threshold_distance(data)	Get the maximum nearest neighbor distance.
libpysal.weights.lat2SW([nrows, ncols, ...])	Create a sparse W matrix for a regular lattice.
libpysal.weights.w_local_cluster(w)	Local clustering coefficients for each unit as a node in a graph.
libpysal.weights.higher_order_sp(w[, k, ...])	Contiguity weights for either a sparse W or W for order k.
libpysal.weights.hexLat2W([nrows, ncols])	Create a W object for a hexagonal lattice.
libpysal.weights.attach_islands(w, w_knn1, ...)	Attach nearest neighbor to islands in spatial weight w.
libpysal.weights.nonplanar_neighbors(w, ...)	Detect neighbors for non-planar polygon collections
libpysal.weights.fuzzy_contiguity(gdf[, ...])	Fuzzy contiguity spatial weights
libpysal.weights.min_threshold_dist_from_shapefile(...)	Get the maximum nearest neighbor distance between observations in the shapefile.
libpysal.weights.build_lattice_shapefile(...)	Build a lattice shapefile with nrows rows and ncols cols.
libpysal.weights.spw_from_gal(galfile)	Sparse scipy matrix for w from a gal file.
libpysal.weights.neighbor_equality(w1, w2)	Test if the neighbor sets are equal between two weights objects

Set Theoretic Weights

libpysal.weights.w_union(w1, w2, **kwargs)	Returns a binary weights object, w, that includes all neighbor pairs that exist in either w1 or w2.
libpysal.weights.w_intersection(w1, w2[, ...])	Returns a binary weights object, w, that includes only those neighbor pairs that exist in both w1 and w2.
libpysal.weights.w_difference(w1, w2[, ...])	Returns a binary weights object, w, that includes only neighbor pairs in w1 that are not in w2.
libpysal.weights.w_symmetric_difference(w1, w2)	Returns a binary weights object, w, that includes only neighbor pairs that are not shared by w1 and w2.
libpysal.weights.w_subset(w1, ids, **kwargs)	Returns a binary weights object, w, that includes only those observations in ids.
libpysal.weights.w_clip(w1, w2[, outSP])	Clip a continuous W object (w1) with a different W object (w2) so only cells where w2 has a non-zero value remain with non-zero values in w1.

Spatial Lag

libpysal.weights.lag_spatial(w, y)	Spatial lag operator.
libpysal.weights.lag_categorical(w, y[, ties])	Spatial lag operator for categorical variables.

cg: Computational Geometry

alpha_shapes

libpysal.cg.alpha_shape(xys, alpha)	Alpha-shape delineation (Edelsbrunner, Kirkpatrick & Seidel, 1983) from a collection of points
libpysal.cg.alpha_shape_auto(xys[, step, ...])	Computation of alpha-shape delineation with automated selection of alpha.

voronoi

libpysal.cg.voronoi_frames(geometry[, ...])

Create Voronoi polygons from a GeoSeries of points, lines, or polygons.

sphere

libpysal.cg.RADIUS_EARTH_KM	Convert a string or number to a floating point number, if possible.
libpysal.cg.RADIUS_EARTH_MILES	Convert a string or number to a floating point number, if possible.
libpysal.cg.arcdist(pt0, pt1[, radius])	Arc distance between two points on a sphere.
libpysal.cg.arcdist2linear(arc_dist[, radius])	Convert an arc distance (spherical earth) to a linear distance (R3) in the unit sphere.
libpysal.cg.brute_knn(pts, k[, mode, radius])	Computes a brute-force \(k\) nearest neighbors.
libpysal.cg.fast_knn(pts, k[, return_dist, ...])	Computes \(k\) nearest neighbors on a sphere.
libpysal.cg.fast_threshold(pts, dist[, radius])	Find all neighbors on a sphere within a threshold distance.
libpysal.cg.linear2arcdist(linear_dist[, radius])	Convert a linear distance in the unit sphere (R3) to an arc distance based on supplied radius.
libpysal.cg.toLngLat(xyz)	Convert a point's x,y,z to latitude and longitude.
libpysal.cg.toXYZ(pt)	Convert a point's latitude and longitude to x,y,z.
libpysal.cg.lonlat(pointslist)	Converts point order from lat-lon tuples to lon-lat (x,y) tuples.
libpysal.cg.harcdist(p0, p1[, lonx, radius])	Alternative the arc distance function, uses the haversine formula.
libpysal.cg.geointerpolate(p0, p1, t[, lonx])	Finds a point on a sphere along the great circle distance between two points on a sphere also known as a way point in great circle navigation.
libpysal.cg.geogrid(pup, pdown, k[, lonx])	Computes a \(k+1\) by \(k+1\) set of grid points for a bounding box in lat-lon.

shapes

libpysal.cg.Point(loc)	Geometric class for point objects.
libpysal.cg.LineSegment(start_pt, end_pt)	Geometric representation of line segment objects.
libpysal.cg.Line(m, b)	Geometric representation of line objects.
libpysal.cg.Ray(origin, second_p)	Geometric representation of ray objects.
libpysal.cg.Chain(vertices)	Geometric representation of a chain, also known as a polyline.
libpysal.cg.Polygon(vertices[, holes])	Geometric representation of polygon objects.
libpysal.cg.Rectangle(left, lower, right, upper)	Geometric representation of rectangle objects.
libpysal.cg.asShape(obj)	Returns a PySAL shape object from obj, which must support the __geo_interface__.

standalone

libpysal.cg.bbcommon(bb, bbother)	Old Stars method for bounding box overlap testing.
libpysal.cg.get_bounding_box(items)	Find bounding box for a list of geometries.
libpysal.cg.get_angle_between(ray1, ray2)	Returns the angle formed between a pair of rays which share an origin.
libpysal.cg.is_collinear(p1, p2, p3)	Returns whether a triplet of points is collinear.
libpysal.cg.get_segments_intersect(seg1, seg2)	Returns the intersection of two segments if one exists.
libpysal.cg.get_segment_point_intersect(seg, pt)	Returns the intersection of a segment and point.
libpysal.cg.get_polygon_point_intersect(poly, pt)	Returns the intersection of a polygon and point.
libpysal.cg.get_rectangle_point_intersect(...)	Returns the intersection of a rectangle and point.
libpysal.cg.get_ray_segment_intersect(ray, seg)	Returns the intersection of a ray and line segment.
libpysal.cg.get_rectangle_rectangle_intersection(r0, r1)	Returns the intersection between two rectangles.
libpysal.cg.get_polygon_point_dist(poly, pt)	Returns the distance between a polygon and point.
libpysal.cg.get_points_dist(pt1, pt2)	Returns the distance between a pair of points.
libpysal.cg.get_segment_point_dist(seg, pt)	Returns (1) the distance between a line segment and point and (2) the distance along the segment to the closest location on the segment from the point as a ratio of the length of the segment.
libpysal.cg.get_point_at_angle_and_dist(ray, ...)	Returns the point at a distance and angle relative to the origin of a ray.
libpysal.cg.convex_hull(points)	Returns the convex hull of a set of points.
libpysal.cg.is_clockwise(vertices)	Returns whether a list of points describing a polygon are clockwise or counterclockwise.
libpysal.cg.point_touches_rectangle(point, rect)	Returns True (1) if the point is in the rectangle or touches it's boundary, otherwise False (0).
libpysal.cg.get_shared_segments(poly1, poly2)	Returns the line segments in common to both polygons.
libpysal.cg.distance_matrix(X[, p, threshold])	Calculate a distance matrix.

locators

libpysal.cg.Grid(bounds, resolution)	Representation of a binning data structure.
libpysal.cg.PointLocator(points)	An abstract representation of a point indexing data structure.
libpysal.cg.PolygonLocator(polygons)	An abstract representation of a polygon indexing data structure.

kdtree

libpysal.cg.KDTree(data[, leafsize, ...])

kd-tree built on top of kd-tree functionality in scipy.

io

libpysal.io.open	alias of FileIO
libpysal.io.fileio.FileIO([dataPath, mode, ...])	Metaclass for supporting spatial data file read and write.

examples

libpysal.examples.available()	Return a dataframe with available datasets.
libpysal.examples.explain(name)	Explain a dataset by name.
libpysal.examples.get_path(file_name)	Get the path for a file by searching installed datasets.