Book Image

Practical Data Wrangling

By : Allan Visochek
Book Image

Practical Data Wrangling

By: Allan Visochek

Overview of this book

Around 80% of time in data analysis is spent on cleaning and preparing data for analysis. This is, however, an important task, and is a prerequisite to the rest of the data analysis workflow, including visualization, analysis and reporting. Python and R are considered a popular choice of tool for data analysis, and have packages that can be best used to manipulate different kinds of data, as per your requirements. This book will show you the different data wrangling techniques, and how you can leverage the power of Python and R packages to implement them. You’ll start by understanding the data wrangling process and get a solid foundation to work with different types of data. You’ll work with different data structures and acquire and parse data from various locations. You’ll also see how to reshape the layout of data and manipulate, summarize, and join data sets. Finally, we conclude with a quick primer on accessing and processing data from databases, conducting data exploration, and storing and retrieving data quickly using databases. The book includes practical examples on each of these points using simple and real-world data sets to give you an easier understanding. By the end of the book, you’ll have a thorough understanding of all the data wrangling concepts and how to implement them in the best possible way.
Table of Contents (16 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Chapter 5. Manipulating Text Data - An Introduction to Regular Expressions

Previous chapters have dealt with data manipulation of data on a macroscopic level, without much emphasis on the values in each data entry. In other words, the content up until this point has focused with processing datasets as a whole.

In these next two chapters, I will discuss data wrangling on a more microscopic level, placing emphasis on the individual values of the dataset. This chapter will be about working with text data. In this chapter, I will introduce and discuss the use of regularexpressions to recognize patterns in strings. After a brief introduction of regular expressions, I will demonstrate a specific application of regular expressions in a project to extract street names from a dataset containing addresses.

This chapter will include the following sections:

  • Logistical overview
  • Understanding the need for pattern recognition
  • Introducing regular expressions
  • Looking for patterns
  • Quantifying the existence of patterns...