web5design / graphlib

A directed multi-graph library for JavaScript

Graphlib

Graphlib is a JavaScript library that provides data structures for undirected and directed multi-graphs along with algorithms that can be used with them.

Note that graphlib is current a pre-1.0.0 library. We will do our best to maintain backwards compatibility for patch level increases (e.g. 0.0.1 to 0.0.2) but make no claim to backwards compatibility across minor releases (e.g. 0.0.1 to 0.1.0). Watch our CHANGELOG for details on changes.

Getting Graphlib

NPM Install

Before installing this library you need to install the npm package manager.

To get graphlib from npm, use:

$ npm install graphlib

Browser Scripts

You can get the latest browser-ready scripts:

• graphlib.js
• graphlib.min.js

Build From Source

Before building this library you need to install the npm package manager.

Check out this project and run this command from the root of the project:

$ make

This will generate graphlib.js and graphlib.min.js in the out/dist directory of the project.

Example

var Digraph = require("graphlib").Digraph;

// Create a new empty graph
var g = new Digraph();

// Add node "A" to the graph with no value
g.addNode("A");

// This returns true
g.hasNode("A");

// Add node "B" to the graph with a String value
g.addNode("B", "B's value");

// Prints `B's value`
console.log(g.node("B"));

// Add node "C" to the graph with an Object value
g.addNode("C", { k: 123 });
g.addNode("D");

// Prints `[ 'A', 'B', 'C', 'D' ]`
console.log(g.nodes());

// Add a directed edge with the ID "AB" from "A" to "B", but assign no value
g.addEdge("AB", "A", "B");

// Add a directed edge with no ID (Diraph will assign one) from "B" to "C"
g.addEdge(null, "B", "C");

// Add a directed edge from "C" to "D" with an Object value
g.addEdge("CD", "C", "D", { k: 456 });

// Since Digraph is a multi-graph, we can have multiple edges incident on the
// same source and target nodes.
g.addEdge("AB2", "A", "B");

// Prints `[ 'AB', '_ANON-1', 'CD', 'AB2' ]`. `_ANON-1` is the edge from "B" to "C"
console.log(g.edges());

// Which edges go from "A" to "B"? This prints `[ 'AB', 'AB2' ]`
console.log(g.outEdges("A", "B"));

// Which edges are incident on "D"? This prints `[ 'CD' ]`
console.log(g.incidentEdges("D"));

// How about a subgraph?
var g2 = g.subgraph(["A", "B", "C"]);

// Prints `[ 'A', 'B', 'C' ]`
console.log(g2.nodes());

// Prints `[ 'AB', '_ANON-1', 'AB2' ]`. Note that edges that have both their
// source and target nodes in the graph are also included in the subgraph.
console.log(g2.edges());

API

API documentation

Contributing

We welcome contributions under the MIT license! Here are a few ways you can help:

• Bug reports
• Bug fixes
• New algorithms
• More test cases
• Documentation improvements
• Imrpovements to the core Graph API

If your change involves change to the core Graph API, we recommend discussing the idea via a GitHub issue first.

License

Graphlib is licensed under the terms of the MIT License. See the LICENSE file for details.