Book Image

Data Wrangling with Python

By : Dr. Tirthajyoti Sarkar, Shubhadeep Roychowdhury
Book Image

Data Wrangling with Python

By: Dr. Tirthajyoti Sarkar, Shubhadeep Roychowdhury

Overview of this book

For data to be useful and meaningful, it must be curated and refined. Data Wrangling with Python teaches you the core ideas behind these processes and equips you with knowledge of the most popular tools and techniques in the domain. The book starts with the absolute basics of Python, focusing mainly on data structures. It then delves into the fundamental tools of data wrangling like NumPy and Pandas libraries. You'll explore useful insights into why you should stay away from traditional ways of data cleaning, as done in other languages, and take advantage of the specialized pre-built routines in Python. This combination of Python tips and tricks will also demonstrate how to use the same Python backend and extract/transform data from an array of sources including the Internet, large database vaults, and Excel financial tables. To help you prepare for more challenging scenarios, you'll cover how to handle missing or wrong data, and reformat it based on the requirements from the downstream analytics tool. The book will further help you grasp concepts through real-world examples and datasets. By the end of this book, you will be confident in using a diverse array of sources to extract, clean, transform, and format your data efficiently.
Table of Contents (12 chapters)
Data Wrangling with Python
Preface
Appendix

Advanced List Comprehension and the zip Function


In this topic, we will deep dive into the heart of list comprehension. We have already seen a basic form of it, including something as simple as a = [i for i in range(0, 30)] to something a bit more complex that involves one conditional statement. However, as we already mentioned, list comprehension is a very powerful tool and, in this topic, we will explore the power of this amazing tool further. We will investigate another close relative of list comprehension called generators, and also work with zip and its related functions and methods. By the end of this topic, you will be confident in handling complicated logical problems.

Introduction to Generator Expressions

Previously, while discussing advanced data structures, we witnessed functions such as repeat. We said that they represent a special type of function known as iterators. We also showed you how the lazy evaluation of an iterator can lead to an enormous amount of space saving and time...