nneighb: Find nearest neighbors

In kdtools: Tools for Working with Multidimensional Data

Description

Find nearest neighbors

Usage

kd_nearest_neighbors(x, v, n, ...)

## S3 method for class 'matrix'
kd_nearest_neighbors(x, v, n, cols = NULL, alpha = 0, ...)

## S3 method for class 'arrayvec'
kd_nearest_neighbors(x, v, n, ...)

## S3 method for class 'data.frame'
kd_nearest_neighbors(x, v, n, cols = NULL, w = NULL, ...)

kd_nn_indices(x, v, n, ...)

## S3 method for class 'arrayvec'
kd_nn_indices(x, v, n, distances = FALSE, ...)

## S3 method for class 'matrix'
kd_nn_indices(x, v, n, cols = NULL, distances = FALSE, alpha = 0, ...)

## S3 method for class 'data.frame'
kd_nn_indices(x, v, n, cols = NULL, w = NULL, distances = FALSE, ...)

kd_nearest_neighbor(x, v)

## S3 method for class 'matrix'
kd_nearest_neighbor(x, v)

## S3 method for class 'arrayvec'
kd_nearest_neighbor(x, v)

Arguments

x	an object sorted by kd_sort
v	a vector specifying where to look
n	the number of neighbors to return
...	ignored
cols	integer or character vector or formula indicating columns
alpha	approximate neighbors within (1 + alpha)
w	distance weights
distances	return distances as attribute if true

Value

kd_nearest_neighbors	one or more rows from the sorted input
kd_nn_indices	a vector of row indices indicating the result
kd_nearest_neighbor	the row index of the neighbor

Examples

if (has_cxx17()) {
x = matrix(runif(200), 100)
y = matrix_to_tuples(x)
kd_sort(y, inplace = TRUE)
y[kd_nearest_neighbor(y, c(1/2, 1/2)),]
kd_nearest_neighbors(y, c(1/2, 1/2), 3)
y[kd_nn_indices(y, c(1/2, 1/2), 5),]
}

kdtools documentation built on Oct. 8, 2021, 9:07 a.m.