Book Image

Python Data Analysis - Second Edition

By : Ivan Idris
Book Image

Python Data Analysis - Second Edition

By: Ivan Idris

Overview of this book

Data analysis techniques generate useful insights from small and large volumes of data. Python, with its strong set of libraries, has become a popular platform to conduct various data analysis and predictive modeling tasks. With this book, you will learn how to process and manipulate data with Python for complex analysis and modeling. We learn data manipulations such as aggregating, concatenating, appending, cleaning, and handling missing values, with NumPy and Pandas. The book covers how to store and retrieve data from various data sources such as SQL and NoSQL, CSV fies, and HDF5. We learn how to visualize data using visualization libraries, along with advanced topics such as signal processing, time series, textual data analysis, machine learning, and social media analysis. The book covers a plethora of Python modules, such as matplotlib, statsmodels, scikit-learn, and NLTK. It also covers using Python with external environments such as R, Fortran, C/C++, and Boost libraries.
Table of Contents (22 chapters)
Python Data Analysis - Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
Key Concepts
Online Resources

About NLTK


NLTK is a Python API for the analysis of texts written in natural languages, such as English. NLTK was created in 2001 and was originally intended as a teaching tool.

Although we installed NLTK in the previous section, we are not done yet; we still need to download the NLTK corpora. The download is relatively large (about 1.8 GB); however, we only have to download it once. Unless you know exactly which corpora you require, it's best to download all the available corpora. Download the corpora from the Python shell as follows:

$ python3
>>> import nltk 
>>> nltk.download()

A GUI application should appear, where you can specify a destination and what file to download.

If you are new to NLTK, it's most convenient to choose the default option and download everything. In this chapter, we will need the stopwords, movie reviews, names, and Gutenberg corpora. Readers are encouraged to follow the sections in the ch-09.ipynb file.