Book Image

NLTK Essentials

By : Nitin Hardeniya
Book Image

NLTK Essentials

By: Nitin Hardeniya

Overview of this book

<p>Natural Language Processing (NLP) is the field of artificial intelligence and computational linguistics that deals with the interactions between computers and human languages. With the instances of human-computer interaction increasing, it’s becoming imperative for computers to comprehend all major natural languages. Natural Language Toolkit (NLTK) is one such powerful and robust tool.</p> <p>You start with an introduction to get the gist of how to build systems around NLP. We then move on to explore data science-related tasks, following which you will learn how to create a customized tokenizer and parser from scratch. Throughout, we delve into the essential concepts of NLP while gaining practical insights into various open source tools and libraries available in Python for NLP. You will then learn how to analyze social media sites to discover trending topics and perform sentiment analysis. Finally, you will see tools which will help you deal with large scale text.</p> <p>By the end of this book, you will be confident about NLP and data science concepts and know how to apply them in your day-to-day work.</p>
Table of Contents (17 chapters)
NLTK Essentials
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Data extraction


Some of the most commonly used fields of interest in data extraction are:

  • text: This is the content of the tweet provided by the user

  • user: These are some of the main attributes about the user, such as username, location, and photos

  • Place: This is where the tweets are posted, and also the geo coordinates

  • Entities: Effectively, these are the hashtags and topics that a user attaches to his / her tweets

Every attribute in the previous figure can be a good use case for some of the social mining exercises done in practice. Let's jump onto the topic of how we can get to these attributes and convert them to a more readable form, or how we can process some of these:

Source: tweetinfo.py

>>>import json
>>>import sys
>>>tweets = json.loads(open(sys.argv[1]).read())

>>>tweet_texts = [ tweet['text']\
                               for tweet in tweets ]
>>>tweet_source = [tweet ['source'] for tweet in tweets]
>>>tweet_geo = [tweet...