R: rdist: an R package for distances

rdist {rdist} | R Documentation

## rdist: an R package for distances

### Description

`rdist` provide a common framework to calculate distances. There are three main functions:

- `rdist` computes the pairwise distances between observations in one matrix and returns a `dist` object,

- `pdist` computes the pairwise distances between observations in one matrix and returns a `matrix`, and

- `cdist` computes the distances between observations in two matrices and returns a `matrix`.

In particular the `cdist` function is often missing in other distance functions. All calculations involving `NA` values will consistently return `NA`.

### Usage

    rdist(X, metric = "euclidean", p = 2L)

    pdist(X, metric = "euclidean", p = 2)

    cdist(X, Y, metric = "euclidean", p = 2)

### Arguments

`X, Y` | A matrix
`metric` | The distance metric to use
`p` | The power of the Minkowski distance

### Details

Available distance measures are (written for two vectors v and w):

- `"euclidean"`: sqrt(sum_i((v_i - w_i)^2))

- `"minkowski"`: (sum_i(|v_i - w_i|^p))^{1/p}

- `"manhattan"`: sum_i(|v_i-w_i|)

- `"maximum"` or `"chebyshev"`: max_i(|v_i-w_i|)

- `"canberra"`: sum_i(|v_i-w_i|/(|v_i|+|w_i|))

- `"angular"`: arccos(cor(v, w))

- `"correlation"`: sqrt((1-cor(v, w))/2)

- `"absolute_correlation"`: sqrt((1-|cor(v, w)|^2))

- `"hamming"`: sum_i(v_i != w_i)/sum_i(1)

- `"jaccard"`: sum_i(v_i != w_i)/sum_i(v_i != 0 or w_i != 0)

- Any function that defines a distance between two vectors.

[Package rdist version 0.0.5 Index]