Book Image

Python Feature Engineering Cookbook

By : Soledad Galli
Book Image

Python Feature Engineering Cookbook

By: Soledad Galli

Overview of this book

Feature engineering is invaluable for developing and enriching your machine learning models. In this cookbook, you will work with the best tools to streamline your feature engineering pipelines and techniques and simplify and improve the quality of your code. Using Python libraries such as pandas, scikit-learn, Featuretools, and Feature-engine, you’ll learn how to work with both continuous and discrete datasets and be able to transform features from unstructured datasets. You will develop the skills necessary to select the best features as well as the most suitable extraction techniques. This book will cover Python recipes that will help you automate feature engineering to simplify complex processes. You’ll also get to grips with different feature engineering strategies, such as the box-cox transform, power transform, and log transform across machine learning, reinforcement learning, and natural language processing (NLP) domains. By the end of this book, you’ll have discovered tips and practical solutions to all of your feature engineering problems.
Table of Contents (13 chapters)

Deriving representations of the year and month

Some events occur more often at certain times of the year, for example, recruitment rates increase after Christmas and slow down toward the summer holidays in Europe. Businesses and organizations want to evaluate performance and objectives at regular intervals throughout the year, for example, at every quarter or every semester. Therefore, deriving these features from a date variable is very useful for both data analysis and machine learning. In this recipe, we will learn how to derive the year, month, quarter, and semester from a datetime variable using pandas and NumPy.

How to do it...

To proceed with the recipe, let's import the libraries and create a toy dataset:

  1. Import...