AI for PHP Developers (examples)AI for PHP

Introduction

• Getting Started • ML Ecosystem in PHP

Part I. The Mathematical Language of AI

• What is a model
• Vectors, dimensions and feature spaces
• Distances and similarity

Part II. Learning as Optimization

• Error, loss functions, and why they are needed
• Linear regression as a basic model
• Gradient descent on fingers

Part III. Classification and probabilities

• Probability as degree of confidence
• Logistic regression
• Why Naive Bayes works

Part IV. Proximity and data structure

• The k-nearest neighbors algorithm and local solutions
• Decision Trees and space partitioning

Part V. Text as mathematics

• Why do words turn into numbers
• Bag of Words and TF–IDF
• Embeddings as continuous spaces of meaning
• Transformers and context: from static vectors to understanding meaning
• Hands-on: embeddings in PHP with transformers
• RAG: Retrieval-Augmented Generation as an engineering system

Home
Part V. Text as mathematics
Why do words turn into numbers

Why do words turn into numbers

There are no runnable examples or code in this chapter because it is a concept, not a hands-on implementation.