nn2: Extension of nn method for two matrices

In talegari/disto: Unified Interface to Distance, Dissimilarity, Similarity Matrices

Description

Find k or fixed radius nearest neighbors of each observation(row) matrix y in matrix x

Usage

nn2(x, y, k, r, method = "euclidean", ...)

Arguments

x	Numeric matrix
y	Numneric matrix
k	Number of nearest neighbors
r	Radius for nearest neighbors
method	(string or function) Distance metric passed to 'proxy::dist'
...	Additional arguments are sent to pbmclapply

Details

Exactly one among k or r has to be provided

Value

Object of class 'nn'. A list with these elements:

• triplet: Matrix with three columns: row, col and distance. For a fixed observation of matrix y (value in 'row'), all corresponding values in 'col' are the indexes of the nearest neighbors in matrix x. All corresponding values in 'distance' are the distances to those nearest neighbors

• size: Number of rows of matrix y

• sizeX: Number of rows of matrix x

• k or r : Depending on the input

Examples

temp <- nn2(x = matrix(rnorm(1e4), ncol = 10)
            , y = matrix(runif(1e3), ncol = 10)
            , r = 2
            )
temp

talegari/disto documentation built on May 10, 2019, 3:19 a.m.