@thi.ng/k-means

This project is part of the @thi.ng/umbrella monorepo.

• About
• Status
• Installation
• Dependencies
• Usage examples
• API
• Authors
• License

About

Configurable k-means & k-medians (with k-means++ initialization) for n-D vectors.

Status

BETA - possibly breaking changes forthcoming

Search or submit any issues for this package

Installation

yarn add @thi.ng/k-means

ES module import:

<script type="module" src="https://cdn.skypack.dev/@thi.ng/k-means"></script>

Skypack documentation

For Node.js REPL:

const kMeans = await import("@thi.ng/k-means");

Package sizes (brotli'd, pre-treeshake): ESM: 906 bytes

Dependencies

• @thi.ng/api
• @thi.ng/distance
• @thi.ng/errors
• @thi.ng/random
• @thi.ng/vectors

Usage examples

Several demos in this repo's /examples directory are using this package.

A selection:

Screenshot	Description	Live demo	Source
	Color palette generation via dominant color extraction from uploaded images	Demo	Source
	Image dithering and remapping using indexed palettes	Demo	Source

API

Generated API docs

Example usage:

import { kmeans, meansLatLon } from "@thi.ng/k-means";
import { HAVERSINE_LATLON } from "@thi.ng/distance";

// data from: https://simplemaps.com/data/world-cities
const items = [
    { id: "berlin", latlon: [52.5167, 13.3833] },
    { id: "boston", latlon: [42.3188, -71.0846] },
    { id: "detroit", latlon: [42.3834, -83.1024] },
    { id: "kyoto", latlon: [35.0111, 135.7669] },
    { id: "london", latlon: [51.5072, -0.1275] },
    { id: "new york", latlon: [40.6943, -73.9249] },
    { id: "osaka", latlon: [34.6936, 135.5019] },
    { id: "paris", latlon: [48.8566, 2.3522] },
    { id: "philadelphia", latlon: [40.0077, -75.1339] },
    { id: "tokyo", latlon: [35.6897, 139.6922] },
    { id: "vienna", latlon: [48.2083, 16.3731] },
];

// cluster based on lat/lon
const clusters = kmeans(
    3,
    items.map((x) => x.latlon),
    {
        // custom centroid calc for geo locations
        // https://docs.thi.ng/umbrella/k-means/modules.html#meansLatLon
        strategy: meansLatLon,
        // custom distance function for geo location (default: DIST_SQ)
        dist: HAVERSINE_LATLON
    }
);

// print each cluster
for (let c of clusters) {
    console.log(c.items.map((i) => items[i].id));
}

// [ 'boston', 'detroit', 'new york', 'philadelphia' ]
// [ 'kyoto', 'osaka', 'tokyo' ]
// [ 'berlin', 'london', 'paris', 'vienna' ]

Authors

• Karsten Schmidt

If this project contributes to an academic publication, please cite it as:

@misc{thing-k-means,
  title = "@thi.ng/k-means",
  author = "Karsten Schmidt",
  note = "https://thi.ng/k-means",
  year = 2021
}

License

© 2021 - 2022 Karsten Schmidt // Apache License 2.0