Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Python Feature Engineering Cookbook

You're reading from   Python Feature Engineering Cookbook Over 70 recipes for creating, engineering, and transforming features to build machine learning models

Arrow left icon
Product type Paperback
Published in Oct 2022
Publisher Packt
ISBN-13 9781804611302
Length 386 pages
Edition 2nd Edition
Languages
Tools
Arrow right icon
Author (1):
Arrow left icon
Soledad Galli Soledad Galli
Author Profile Icon Soledad Galli
Soledad Galli
Arrow right icon
View More author details
Toc

Table of Contents (14) Chapters Close

Preface 1. Chapter 1: Imputing Missing Data 2. Chapter 2: Encoding Categorical Variables FREE CHAPTER 3. Chapter 3: Transforming Numerical Variables 4. Chapter 4: Performing Variable Discretization 5. Chapter 5: Working with Outliers 6. Chapter 6: Extracting Features from Date and Time Variables 7. Chapter 7: Performing Feature Scaling 8. Chapter 8: Creating New Features 9. Chapter 9: Extracting Features from Relational Data with Featuretools 10. Chapter 10: Creating Features from a Time Series with tsfresh 11. Chapter 11: Extracting Features from Text Variables 12. Index 13. Other Books You May Enjoy

Creating features with aggregation primitives

Throughout this chapter, we’ve created features automatically by transforming existing variables into new features. For example, we extracted date and time parts from datetime variables, we counted the number of words, characters, and punctuation in a text, and we combined numerical features into new variables. To create these features, we worked with transform primitives.

Featuretools also supports aggregation primitives. These primitives take related observations as input and return a single value. For example, if we have a numerical variable, price, related to an invoice, an aggregation primitive would take all the price observations for a single invoice and return a single value, such as the mean price or the sum (that is, the total amount paid), for that particular invoice.

Tip

The Featuretools aggregation functionality is the equivalent of groupby in pandas, followed by pandas functions such as mean, sum, std, and...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime
Banner background image