ndarray-distance

    1.0.0 • Public • Published

    ndarray-distance

    Computes the Lp distance between two ndarrays. Works both in node.js and in browserify.

    build status

    Example

    var distance = require("ndarray-distance")
    var ndarray = require("ndarray")
     
    //Create two arrays
    var a = ndarray([1, 2, 3, 4, 5])
    var b = ndarray([0, 2, 3, 10, 6])
     
     
    //First compute sum of squared distances
    var l2Dist = distance(a, b)
     
    //Can also compute l1 distance (absolute difference)
    var l1Dist = distance(a, b, 1)
     
    //And maximum distance
    var linfDist = distance(a, b, Infinity)
     
    //And any other Lp distance as well
    var l3Dist = distance(a, b, 3)

    Install

    Install using npm:

    npm install ndarray-distance
    

    API

    require("ndarray-distance")(a, b[, p])

    Computes the Lp distance between two ndarrays a and b. That is,

    dist(a,b,p) = ( sum |a[i] - b[i]|^p )^(1/p)
    

    Note that here a and b do not have to be vectors and can be images or volumes.

    • a and b are both ndarrays with the same shape
    • p is a parameter that determines the exponent of the metric. The default value is p=2

    Special values of p include:

    • p=0 which counts the number of entries where a and b differ
    • p=1 which is the absolute difference between a and b
    • p=2 which is the ordinary Euclidean sum of squared differences
    • p=Infinity which is the maximum absolute difference between a and b

    Returns The Lp distance between a and b

    License

    (c) 2014 Mikola Lysenko. MIT License

    Install

    npm i ndarray-distance

    DownloadsWeekly Downloads

    17

    Version

    1.0.0

    License

    MIT

    Last publish

    Collaborators

    • mikolalysenko
    • rreusser
    • planeshifter
    • jaspervdg
    • hughsk
    • substack