🌐 NetworkXJS - A Graph Library for JavaScript

NetworkXJS is a JavaScript library for working with graph data structures and graph algorithms, inspired by Python's NetworkX. It provides an easy-to-use API for building, analyzing, and manipulating graphs in JavaScript.

🚀 Why NetworkXJS?

• Simple & Flexible: Designed for both beginners and advanced users.
• Strict Graph Handling: No implicit node creation. Nodes must be explicitly added.
• Supports Node & Edge Attributes: Store metadata on both nodes and edges.
• Fast & Lightweight: Uses Map and Set for efficient graph operations.
• No Dependencies: Works in both Node.js and Browser environments.

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📦 Installation

To use NetworkXJS, simply install it via npm or pnpm:

# Using npm
npm install networkxjs

# Using pnpm
pnpm add networkxjs

In browser environments, you can include the library via a CDN:

<script src="/url/to/networkxjs.umd.js"></script>
<script>
  const G = new NetworkXJS.Graph();
  G.addNode(1);
  G.addEdge(1, 2);
  console.log(G.hasEdge(1, 2));  // true
</script>

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🚀 Quick Start

1️⃣ Import the library

import { Graph } from 'networkxjs';

// OR (if using CommonJS)
const { Graph } = require('networkxjs');

2️⃣ Create a graph

const G = new Graph();

G.addNode(1, { color: "red" });
G.addNode("A", { color: "blue" });

console.log(G.hasNode(1));  // true
console.log(G.hasNode("B"));  // false

3️⃣ Add edges

G.addEdge(1, "A", { weight: 5 });
console.log(G.hasEdge(1, "A")); // true

// Retrieve edge attributes
console.log(G.edge(1, "A")); // { weight: 5 }

4️⃣ Remove nodes & edges

G.removeEdge(1, "A");
console.log(G.hasEdge(1, "A")); // false

G.removeNode("A");
console.log(G.hasNode("A")); // false

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🎯 API Reference

🔹 Graph Methods

Method	Description
addNode(id, attr={})	Add a node with an optional attribute object.
addNodesFrom([...])	Add multiple nodes at once.
hasNode(id)	Check if a node exists.
node(id)	Get node attributes (throws if not found).
removeNode(id)	Remove a node and all connected edges.
addEdge(u, v, attr={})	Add an undirected edge (nodes must exist).
hasEdge(u, v)	Check if an edge exists.
edge(u, v)	Get edge attributes (throws if not found).
removeEdge(u, v)	Remove an edge.
neighbors(id)	Get all neighbors of a node.
numberOfNodes()	Get the total number of nodes.
numberOfEdges()	Get the total number of edges.

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🛠 Common Issues & FAQs

❓ Why do I get an error when adding an edge?

NetworkXJS does not auto-create nodes. You must add both nodes before adding an edge.

const G = new Graph();
G.addNode(1);
G.addNode(2);
G.addEdge(1, 2);  // ✅ Works fine

G.addEdge(3, 4);  // ❌ Error: Node "3" does not exist.

❓ Can I use objects as node IDs?

No. Node IDs must be strings or numbers to ensure fast lookups.

❓ Does it support directed graphs?

Not yet. Future versions may include DiGraph.

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👥 Contributing

We welcome contributions! To contribute:

1. Fork the repository on GitHub.
2. Clone your fork and install dependencies:

   git clone https://github.com/yourusername/networkxjs.git
   cd networkxjs
   pnpm install

3. Run tests before submitting a PR:

   pnpm test

4. Submit a pull request 🎉

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📜 License

This project is licensed under the MIT License.