Fast.ai – Complete Beginner’s Guide
Simplified Deep Learning – AWS Marketplace Edition
What is Fast.ai?
Fast.ai is a high-level deep learning library built on PyTorch that makes AI accessible to everyone. Designed with the ยซpractice first, theory laterยป principle.
Your Learning Progress
Installation Complete
Environment configured and validated
First Steps
Learn to activate environment and use Jupyter
Your First Model
Train an image classifier
Personal Project
Apply Fast.ai to your own dataset
AWS Production
Deploy models to the cloud
Getting Started – Start in 5 Minutes!
Activate the Environment
First, activate your Fast.ai virtual environment:
You’ll see (fastai_env) in your terminal when active.
Start Jupyter Lab
Launch the interactive development environment:
Open your browser at: http://your-ip:8888
Your First Code!
Create a new notebook and test this code:
# Your first vision model in 5 lines
from fastai.vision.all import *
# 1. Download example data (pets dataset)
path = untar_data(URLs.PETS)/'images'
# 2. Create DataLoaders automatically
dls = ImageDataLoaders.from_name_re(
path, get_image_files(path),
pat=r'(.+)_\d+.jpg$',
item_tfms=Resize(460),
batch_tfms=aug_transforms(size=224)
)
# 3. Create pre-trained model
learn = vision_learner(dls, resnet34, metrics=error_rate)
# 4. Find optimal learning rate
learn.lr_find()
# 5. Train the model (4 epochs)
learn.fine_tune(4)
# Sentiment analysis with text
from fastai.text.all import *
# 1. Movie reviews data
path = untar_data(URLs.IMDB)
# 2. Create DataLoaders for text
dls = TextDataLoaders.from_folder(
path, valid='test',
text_vocab=Vocab.create(size=10000),
seq_len=72
)
# 3. Language model
learn = text_classifier_learner(
dls, AWD_LSTM,
drop_mult=0.5,
metrics=accuracy
)
# 4. Progressive training
learn.fit_one_cycle(1, 2e-2)
learn.freeze_to(-2)
learn.fit_one_cycle(1, slice(1e-2/(2.6**4), 1e-2))
# Prediction with tabular data
from fastai.tabular.all import *
import pandas as pd
# 1. Load data (Titanic example)
path = untar_data(URLs.TITANIC)
df = pd.read_csv(path/'train.csv')
# 2. Define categorical and continuous variables
cat_names = ['Sex', 'Embarked', 'Pclass']
cont_names = ['Age', 'Fare', 'SibSp', 'Parch']
# 3. Create DataLoaders
dls = TabularDataLoaders.from_df(
df, path, y_names="Survived",
cat_names=cat_names,
cont_names=cont_names,
procs=[Categorify, FillMissing, Normalize]
)
# 4. Model for tabular data
learn = tabular_learner(dls, metrics=accuracy)
# 5. Train
learn.fit_one_cycle(5)
Beginner Use Cases
Fast.ai is perfect for these initial projects:
Image Classification
Recognize objects, animals, products.
Example: Classify fruit photos
Easy 2 hoursSentiment Analysis
Analyze emotions in texts, reviews.
Example: Classify positive/negative tweets
Easy 3 hoursPrice Prediction
Predict values based on features.
Example: House price prediction
Easy 2 hoursStyle Transfer
Apply artistic styles to photos.
Example: Photo in Van Gogh style
Intermediate 4 hoursproject/ โโโ data/ # Your dataset โ โโโ train/ โ โโโ valid/ โโโ notebooks/ # Jupyter notebooks โ โโโ 01_exploration.ipynb โ โโโ 02_training.ipynb โโโ models/ # Saved models โโโ src/ # Source code โ โโโ utils.py โโโ requirements.txt
AWS Optimization Guide
Your Current Instance
You’re running in CPU mode. For real deep learning, use GPU instances:
| Instance Type | GPU | Price/Hour | Best For |
|---|---|---|---|
| g4dn.xlarge | NVIDIA T4 | ~$0.526 | Beginners, Prototyping |
| g5.xlarge | NVIDIA A10G | ~$1.006 | Production, Teams |
| p3.2xlarge | NVIDIA V100 | ~$3.06 | Research, Heavy Training |
| Spot Instances | All types | 60-90% discount | Learning, Batch Jobs |
Essential AWS Commands
Configure AWS CLI
You’ll need: Access Key ID, Secret Access Key, region (e.g., us-east-1)
Upload Data to S3
Download from S3
Monitor GPU Usage
Troubleshooting Guide
Solution: Activate virtual environment first
Solution: For real training, switch to GPU instance or use CPU mode:
Solution: Reduce batch size:
Solution: Optimize CPU performance:
Visit colab.research.google.com and run !pip install fastai
30-Day Learning Path
Week 1: Fundamentals
- Day 1-2: Install and run first examples
- Day 3-4: Understand DataBlocks and DataLoaders
- Day 5-7: Train models on sample datasets
Week 2: Your First Project
- Day 8-10: Choose a personal project
- Day 11-12: Collect and prepare your data
- Day 13-14: Train and evaluate your model
Week 3: Advanced Topics
- Day 15-17: Hyperparameter tuning
- Day 18-20: Model interpretation and debugging
- Day 21-22: Transfer learning techniques
Week 4: Deployment
- Day 23-24: Export models for production
- Day 25-26: Deploy to AWS/GCP
- Day 27-28: Create API endpoints
- Day 29-30: Monitor and improve
๐ Quick Index
- What is Fast.ai?
- Your Progress
- Getting Started
- Use Cases
- AWS Optimization
- Troubleshooting
- Learning Path
- Resources
๐ฏ Quick Actions
โฑ๏ธ Time Estimates
- First model: 15 minutes
- Basic project: 2 hours
- Basic mastery: 1 week
- Advanced project: 1 month
๐ System Status
๐ค PyTorch: 2.9.1
๐ Fast.ai: 2.8.5
๐ฎ GPU: Not detected
๐ Mode: CPU Learning
Additional Resources
AWS Specific Resources
- Amazon SageMaker – Managed ML service
- EC2 GPU Instances – Complete list
- Deep Learning AMI – Pre-configured images
- Spot Instances – Save up to 90%