Module 5PyTorch Foundations

Data Pipeline Design

Build datasets and loaders that support real training loops.

Why this module matters

Many model problems are actually data problems: bad labels, wrong normalization, hidden leakage, and slow input pipelines.

Prerequisites

  • PyTorch basics
  • Basic file handling

Learning objectives

  • Write custom Dataset classes
  • Use transforms and collate_fn intentionally
  • Profile input throughput and worker behavior

Core concepts

Dataset vs DataLoader
Batching and shuffling
Augmentation and leakage

Hands-on practice

  • Create a small image dataset loader
  • Implement train/test transforms
  • Visualize batches before training starts

Expected output

A reusable data pipeline template for later projects.

Study checklist

  • Write custom Dataset classes
  • Use transforms and collate_fn intentionally
  • Profile input throughput and worker behavior

Common mistakes

  • ⚠️ Applying train augmentation to validation data
  • ⚠️ Using too many workers blindly
  • ⚠️ Never inspecting a batch visually

Module rhythm

  • 1. Read the summary and why-it-matters section first.
  • 2. Work through concepts before rushing into practice.
  • 3. Use the checklist to verify real understanding, not just completion.

How to continue

With data flowing correctly, it is time to build a training loop worth keeping.

Back to course overview →

How to use this page well

Treat each module as a compact learning system: understand the intuition, verify the concepts, do one hands-on task, then use the checklist and mistakes section to pressure-test your understanding.