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

Introducing a basic data wrangling work flow


This chapter is about understanding the components of a program that processes data. As mentioned in the introduction, the approach taken here will be to process data on a basic level. A particular emphasis is placed on opening, reading and writing data in this chapter. Later chapters will focus more on exploration and modification of data.

The following is a basic work flow for data wrangling that applies to processing data files. Data wrangling is not necessarily a linear process, but these steps will help to give a frame of reference for the range of tools and approaches that will be demonstrated in this chapter and throughout the rest of the book.

  1. Open the file containing the input data from within the program:
    • In order for a program to gain access to the data in a particular file, the program first needs to interact with the computer's file system to open the file. This is referred to as file I/O and Python has built-in support to make this...