Build a Neural Network from Scratch in Javascript | CodeSignal Learn

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Build a Neural Network from Scratch in Javascript

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4 courses

74 practices

10 hours

Go beyond black boxes! Build Neural Networks from scratch in Javascript. Master every detail, from neurons to backpropagation, and apply your own library to real-world ML challenges.

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Certificate of Achievement

Verified skills you'll gain

INTERMEDIATE

Deep Learning and Neural Networks

INTERMEDIATE

Model Deployment Processes

Tools you'll use

JavaScript

Math.js

Course 1

Neural Networks Fundamentals: Neurons and Layers

5 lessons

18 practices

This course introduces the core building blocks of neural networks. You'll learn what a neuron is, how it processes information, the role of activation functions, and how neurons are organized into layers. By the end, you'll implement a single dense layer from scratch using JavaScript and array operations.

Course 2

The MLP Architecture: Activations & Initialization in JavaScript

4 lessons

17 practices

This course builds upon single layers to construct a complete Multi-Layer Perceptron (MLP). You'll learn to stack layers, explore different activation functions like ReLU and Softmax, and understand the importance of weight initialization for effective training.

Course 3

Training Neural Networks: the Backpropagation Algorithm

5 lessons

21 practices

This course dives into how neural networks learn from data. You'll implement loss functions to measure prediction errors, understand the intuition and mechanics of gradient descent, master the backpropagation algorithm to calculate gradients, and use an optimizer to update network weights.

Course 4

Building and Applying Your Neural Network Library

5 lessons

18 practices

This course focuses on transforming your code into a reusable JavaScript library and applying it to a real-world problem. You'll refactor your existing components into a structured package, build a `Model` class for easier network definition and training, and finally, train your neural network on a real regression dataset.

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