# nndist: Determine nearest neighbors based on maximum distance In smerc: Statistical Methods for Regional Counts

 nndist R Documentation

## Determine nearest neighbors based on maximum distance

### Description

nndist determines the nearest neighbors for a set of observations within a certain radius.

### Usage

nndist(d, ubd)


### Arguments

 d An n\times n square distance matrix containing the intercentroid distance between the n region centroids. ubd A proportion in (0, 1]. The distance of potential clusters must be no more than ubd * m, where m is the maximum intercentroid distance between all coordinates.

### Details

This function determines the nearest neighbors of each centroid based on the intercentroid distance. The number of nearest neighbors is limited by the furthest distance between the starting centroid and the farthest neighbor.

### Value

Returns the indices of the nearest neighbors as a list.

Joshua French

### Examples

data(nydf)
coords <- as.matrix(nydf[, c("longitude", "latitude")])
d <- as.matrix(dist(coords))
nn <- nndist(d, ubd = 0.01)


smerc documentation built on Oct. 13, 2022, 9:07 a.m.