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)

Transforming variables with the logarithm

The logarithm function is commonly used to transform variables. It has a strong effect on the shape of the variable distribution and can only be applied to positive variables. In this recipe, we will learn how to perform logarithmic transformation using NumPy, scikit-learn, and Feature-engine. We will also create a diagnostic plot function to evaluate the effect of the transformation on the variable distribution.

How to do it...

Let's begin by importing the libraries and classes we need and getting the dataset ready:

  1. Import the required Python libraries, classes, and functions:
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
import scipy.stats as stats...