How To Extend Math.js With Plugins?

Math.js is a comprehensive math library for JavaScript and Node.js, designed to handle complex mathematical operations, expressions, and data structures like matrices and units. While Math.js comes with a broad set of built-in functions, there are times when you might need additional functionality designed for your specific needs.

Fortunately, Math.js allows you to extend its capabilities through plugins. In this article, we will see the steps to extend Math.js with plugins, including creating, registering, and using custom functions.

What are Plugins in Math.js?

Plugins in Math.js are custom modules or functions that you can add to the existing Math.js library to extend its functionality. They allow you to create custom operations, define new functions, or even modify existing behaviour in Math.js. This modular approach makes Math.js highly flexible and adaptable for various mathematical and computational needs.

Steps to Extend Math.js with Plugins

Here’s a step-by-step guide to extending Math.js with plugins:

Step 1: Set Up Your Project Directory

First, create a new project directory and navigate into it:

mkdir mathjs-plugin-project
cd mathjs-plugin-project

Step 2: Initialize the Project

Initialize your project with npm to create a package.json file. This file will manage your project dependencies:

npm init -y

Step 3: Install Math.js

Install Math.js using npm:

npm install mathjs

Folder Structure

Dependencies

"dependencies": {
    "mathjs": "^13.1.1"
  }

4. Create a Custom Plugin

To create a custom plugin, you need to define a function or a set of functions in JavaScript that Math.js can recognize and use. Here’s an example of creating a simple plugin that adds a new function to calculate the area of a circle:

//index.js

const math = require('mathjs');
const areaOfCirclePlugin = require('./plugin');

// Create a Math.js instance (optional, but preferred for isolation)
const customMath = math.create(math.all, {});

// Correctly import the plugin
customMath.import(areaOfCirclePlugin);

// Use the custom function
console.log(customMath.areaOfCircle(5));

//plugin.js

// Define the plugin as an object
const areaOfCirclePlugin = {
    areaOfCircle: function (radius) {
        if (radius < 0) {
            throw new Error('Radius must be non-negative');
        }
        return Math.PI * Math.pow(radius, 2);
    }
};

module.exports = areaOfCirclePlugin;

To start the application run the following command.

node src/index.js

Output

78.53981633974483

Best Practices for Extending Math.js with Plugins

• Modularize Plugins: Keep your plugins modular and specific to a task. This makes them reusable and easy to manage.
• Error Handling: Implement robust error handling in your plugins to manage invalid inputs or unexpected behavior.
• Test Your Plugins: Always test your plugins thoroughly with various inputs to ensure they behave as expected.
• Avoid Conflicts: Ensure that your custom functions do not conflict with existing Math.js functions or plugins. Use unique names for your custom functions.
• Documentation: Document your plugins well, including the purpose, usage, and any important notes about their functionality.

Advanced Features with Plugins

• Registering Multiple Plugins: You can register multiple plugins by passing an array of plugins to the math.create() function.
• Custom Types and Data Structures: Beyond functions, you can also define custom types or data structures in Math.js. This allows for more complex extensions like defining new numeric types or operations on matrices.
• Custom Parsing and Evaluation: Extend the Math.js expression parser to add new operators or custom behavior during expression evaluation.