scanstatistics (version 0.1.0)

knn_zones: Find the increasing subsets of \(k\) nearest neighbors for all locations.

Description

Returns the set of increasing nearest neighbor sets for all locations, as a list of integer vectors. That is, for each location the list returned contains one vector containing the location itself, another containing the location and its nearest neighbor, and so on, up to the vector containing the location and its \(k-1\) nearest neighbors.

Usage

knn_zones(k_nearest, .parallel = FALSE, .paropts = NULL)

Arguments

k_nearest

An integer matrix of with \(k\) columns and as many rows as locations. The first element of each row is the integer encoding the location (and equal to the row number); the following elements are the \(k-1\) nearest neighbors in ascending order of distance.

.parallel

if TRUE, apply function in parallel, using parallel backend provided by foreach

.paropts

a list of additional options passed into the foreach function when parallel computation is enabled. This is important if (for example) your code relies on external data or packages: use the .export and .packages arguments to supply them so that all cluster nodes have the correct environment set up for computing.

Value

A list of integer vectors.

Examples

# NOT RUN {
nn <- matrix(c(1L, 2L, 4L, 3L, 5L,
               2L, 1L, 3L, 4L, 5L, 
               3L, 2L, 4L, 1L, 5L,
               4L, 1L, 2L, 3L, 5L,
               5L, 3L, 4L, 2L, 1L),
               ncol = 5, byrow = TRUE)
knn_zones(nn[, 1:3])
# }