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 7. Simplifying Data Manipulation with dplyr

Both R and pandas go a step further to make data manipulation a bit more expressive than most programming languages. For example, many iterative tasks that would otherwise require a for loop (such as selecting a column) can be done using a single line of code.

However, there are still aspects of data manipulation that could be expressed a bit more directly. Recall that in previous chapter, a number of processing steps and variables were used to filter the data and find the result. It can be hard to express a large number of data manipulation operations in a way that is descriptive and contained.

Ideally, it should be possible to express each of the steps for processing data in one sequence of code, and in a way that reflects the function of each processing step. A number of packages build on the R programming language and environment in order to make it more expressive, concise, neat, and consistent. One well developed effort to make data...