libpysal.weights.Relative_Neighborhood¶
- class libpysal.weights.Relative_Neighborhood(coordinates, binary=True, **kwargs)[source]¶
Constructs the Relative Neighborhood graph from a set of points. This graph is a subset of the Delaunay triangulation, where only “relative neighbors” are retained. Further, it is a superset of the Minimum Spanning Tree, with additional “relative neighbors” introduced.
A relative neighbor pair of points i,j must be closer than the maximum distance between i (or j) and each other point k. This means that the points are at least as close to one another as they are to any other point.
- Parameters:
Methods
__init__
(coordinates[, binary])asymmetry
([intrinsic])Asymmetry check.
from_WSP
(WSP[, silence_warnings])Create a pysal W from a pysal WSP object (thin weights matrix).
from_adjlist
(adjlist[, focal_col, ...])Return an adjacency list representation of a weights object.
from_dataframe
(df[, geom_col, ids, use_index])Construct a Delaunay triangulation from a geopandas GeoDataFrame.
from_file
([path, format])Read a weights file into a W object.
from_networkx
(graph[, weight_col])Convert a
networkx
graph to a PySALW
object.from_shapefile
(*args, **kwargs)from_sparse
(sparse)Convert a
scipy.sparse
array to a PySALW
object.full
()Generate a full
numpy.ndarray
.get_transform
()Getter for transform property.
plot
(gdf[, indexed_on, ax, color, node_kws, ...])Plot spatial weights objects.
remap_ids
(new_ids)In place modification throughout
W
of id values fromw.id_order
tonew_ids
in all.set_shapefile
(shapefile[, idVariable, full])Adding metadata for writing headers of
.gal
and.gwt
files.set_transform
([value])Transformations of weights.
symmetrize
([inplace])Construct a symmetric KNN weight.
to_WSP
()Generate a
WSP
object.to_adjlist
([remove_symmetric, drop_islands, ...])Compute an adjacency list representation of a weights object.
to_file
([path, format])Write a weights to a file.
to_networkx
()Convert a weights object to a
networkx
graph.to_sparse
([fmt])Generate a
scipy.sparse
array object from a pysal W.Attributes
asymmetries
List of id pairs with asymmetric weights sorted in ascending index location order.
cardinalities
Number of neighbors for each observation.
component_labels
Store the graph component in which each observation falls.
diagW2
Diagonal of \(WW\).
diagWtW
Diagonal of \(W^{'}W\).
diagWtW_WW
Diagonal of \(W^{'}W + WW\).
histogram
Cardinality histogram as a dictionary where key is the id and value is the number of neighbors for that unit.
id2i
Dictionary where the key is an ID and the value is that ID's index in
W.id_order
.id_order
Returns the ids for the observations in the order in which they would be encountered if iterating over the weights.
id_order_set
Returns
True
if user has setid_order
,False
if not.islands
List of ids without any neighbors.
max_neighbors
Largest number of neighbors.
mean_neighbors
Average number of neighbors.
min_neighbors
Minimum number of neighbors.
n
Number of units.
n_components
Store whether the adjacency matrix is fully connected.
neighbor_offsets
Given the current
id_order
,neighbor_offsets[id]
is the offsets of the id's neighbors inid_order
.nonzero
Number of nonzero weights.
pct_nonzero
Percentage of nonzero weights.
s0
s0
is defined ass1
s1
is defined ass2
s2
is defined ass2array
Individual elements comprising
s2
.sd
Standard deviation of number of neighbors.
sparse
Sparse matrix object.
transform
Getter for transform property.
trcW2
Trace of \(WW\).
trcWtW
Trace of \(W^{'}W\).
trcWtW_WW
Trace of \(W^{'}W + WW\).