libpysal API reference

Spatial Weights

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.

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]) 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 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[, silence_warnings]) 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.

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(*args, …)
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.

Set Theoretic Weights

libpysal.weights.w_union(w1, w2[, …]) 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[, …]) 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(points[, radius]) Composite helper to return Voronoi regions and generator points as individual dataframes

sphere

libpysal.cg.RADIUS_EARTH_KM float(x) -> floating point number
libpysal.cg.RADIUS_EARTH_MILES float(x) -> floating point number
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]) valid modes are [‘arc’,’xrz’]
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 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 arc distance function, uses 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 uses geointerpolate

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.

standalone

libpysal.cg.bbcommon(bb, bbother) Old Stars method for bounding box overlap testing Also defined in pysal.weights._cont_binning
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 get_angle_between(Ray, Ray) -> number
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.
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 the distance between a line segment and point and distance along the segment of the closest point on the segment to 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 if the point is in the rectangle or touches it’s boundary.
libpysal.cg.get_shared_segments(poly1, poly2) Returns the line segments in common to both polygons.
libpysal.cg.distance_matrix(X[, p, threshold]) Distance Matrices

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

examples

libpysal.examples.available([verbose]) List available datasets
libpysal.examples.explain(name) Explain a dataset by name
libpysal.examples.get_path(example_name[, raw]) Get path of example folders