Book Image

Learn Python by Building Data Science Applications

By : Philipp Kats, David Katz
Book Image

Learn Python by Building Data Science Applications

By: Philipp Kats, David Katz

Overview of this book

Python is the most widely used programming language for building data science applications. Complete with step-by-step instructions, this book contains easy-to-follow tutorials to help you learn Python and develop real-world data science projects. The “secret sauce” of the book is its curated list of topics and solutions, put together using a range of real-world projects, covering initial data collection, data analysis, and production. This Python book starts by taking you through the basics of programming, right from variables and data types to classes and functions. You’ll learn how to write idiomatic code and test and debug it, and discover how you can create packages or use the range of built-in ones. You’ll also be introduced to the extensive ecosystem of Python data science packages, including NumPy, Pandas, scikit-learn, Altair, and Datashader. Furthermore, you’ll be able to perform data analysis, train models, and interpret and communicate the results. Finally, you’ll get to grips with structuring and scheduling scripts using Luigi and sharing your machine learning models with the world as a microservice. By the end of the book, you’ll have learned not only how to implement Python in data science projects, but also how to maintain and design them to meet high programming standards.
Table of Contents (26 chapters)
Free Chapter
1
Section 1: Getting Started with Python
11
Section 2: Hands-On with Data
17
Section 3: Moving to Production

Chapter 11

Why, if there is an empty cell in the Pandas column, are integer values in this column converted into floats?

This happens since NumPy (and based on it, Pandas) does not support null integers—every null is a special case of a float. Thus, to keep the datatype consistent across the column, NumPy has to convert all integers into floats.

What is the benefit of plotting missing values?

Often, missing values in a dataset can have a certain pattern—for example, records with a missing value in one column also miss values in others. Having a bird's-eye view allows you to find those patterns and define an appropriate imputation strategy.

What is RegEx? Is it a separate language?

Indeed, Regular Expressions, or regex, is a distinct mini-language for text extraction and search. RegEx is implemented in most programming languages—including Python.

How can...