graphlib

What is graphlib?

The graphlib package is a JavaScript library for creating and manipulating directed and undirected graphs. It provides a variety of methods for graph creation, traversal, and analysis, making it a versatile tool for working with graph data structures.

What are graphlib's main functionalities?

Graph Creation

This feature allows you to create a new graph, add nodes, and create edges between nodes. The code sample demonstrates how to create a graph, add two nodes 'a' and 'b', and create an edge from 'a' to 'b'.

const graphlib = require('graphlib');
const g = new graphlib.Graph();
g.setNode('a');
g.setNode('b');
g.setEdge('a', 'b');
console.log(g.nodes()); // ['a', 'b']
console.log(g.edges()); // [{ v: 'a', w: 'b' }]

Graph Traversal

This feature allows you to traverse the graph using depth-first search (DFS). The code sample demonstrates how to perform a DFS starting from node 'a' and prints the traversal order.

const graphlib = require('graphlib');
const g = new graphlib.Graph();
g.setNode('a');
g.setNode('b');
g.setNode('c');
g.setEdge('a', 'b');
g.setEdge('b', 'c');
const dfs = graphlib.alg.dfs(g, ['a']);
console.log(dfs); // [{ v: 'a' }, { v: 'b' }, { v: 'c' }]

Graph Analysis

This feature allows you to analyze the graph for properties such as acyclicity. The code sample demonstrates how to check if the graph contains cycles and prints the result.

const graphlib = require('graphlib');
const g = new graphlib.Graph();
g.setNode('a');
g.setNode('b');
g.setNode('c');
g.setEdge('a', 'b');
g.setEdge('b', 'c');
g.setEdge('c', 'a');
const isAcyclic = graphlib.alg.isAcyclic(g);
console.log(isAcyclic); // false

Other packages similar to graphlib

cytoscape

Cytoscape is a graph theory library for visualization and analysis. It provides a rich set of features for graph manipulation and visualization, making it more suitable for applications that require interactive graph displays. Compared to graphlib, Cytoscape offers more advanced visualization capabilities but may be more complex to use for simple graph operations.

d3-graphviz

d3-graphviz is a library for rendering graphs described in the DOT language using D3. It is particularly useful for visualizing complex graphs and integrates well with the D3 ecosystem. While graphlib focuses on graph manipulation and analysis, d3-graphviz excels in graph rendering and visualization.

dagre

Dagre is a JavaScript library for laying out directed graphs on the client-side. It is often used in conjunction with graphlib for layout purposes. Dagre provides advanced layout algorithms, making it a good complement to graphlib's graph manipulation capabilities.

README

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.