Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "The nunique() method ignores missing values by default."

A block of code is set as follows:

import pandas as pdfrom sklearn.datasets import load_bostonfrom sklearn.model_selection import train_test_splitfrom sklearn.preprocessing import PolynomialFeatures

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

X_train['A7'] = np.where(X_train['A7'].isin(frequent_cat), X_train['A7'], 'Rare')X_test['A7'] = np.where(X_test['A7'].isin(frequent_cat), ...

Get Python Feature Engineering Cookbook now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.