Book Image

Python Natural Language Processing Cookbook

By : Zhenya Antić
Book Image

Python Natural Language Processing Cookbook

By: Zhenya Antić

Overview of this book

Python is the most widely used language for natural language processing (NLP) thanks to its extensive tools and libraries for analyzing text and extracting computer-usable data. This book will take you through a range of techniques for text processing, from basics such as parsing the parts of speech to complex topics such as topic modeling, text classification, and visualization. Starting with an overview of NLP, the book presents recipes for dividing text into sentences, stemming and lemmatization, removing stopwords, and parts of speech tagging to help you to prepare your data. You’ll then learn ways of extracting and representing grammatical information, such as dependency parsing and anaphora resolution, discover different ways of representing the semantics using bag-of-words, TF-IDF, word embeddings, and BERT, and develop skills for text classification using keywords, SVMs, LSTMs, and other techniques. As you advance, you’ll also see how to extract information from text, implement unsupervised and supervised techniques for topic modeling, and perform topic modeling of short texts, such as tweets. Additionally, the book shows you how to develop chatbots using NLTK and Rasa and visualize text data. By the end of this NLP book, you’ll have developed the skills to use a powerful set of tools for text processing.
Table of Contents (10 chapters)

Constructing word clouds

In this recipe, we will create two word clouds. Both of them will use the text from the The Adventures of Sherlock Holmes book, and one of them will be shaped like a silhouette of Sherlock Holmes' head.

Getting ready

In order to complete this recipe, you will need to install the wordcloud package:

pip install wordcloud

How to do it…

We will define a function to that creates word clouds from text and then use it on the text of The Adventures of Sherlock Holmes:

  1. Import the necessary packages and functions:
    import os
    import nltk
    from os import path
    import matplotlib.pyplot as plt
    from wordcloud import WordCloud, STOPWORDS
    from Chapter01.dividing_into_sentences import read_text_file
    from Chapter01.removing_stopwords import compile_stopwords_list_frequency
  2. Define the create_wordcloud function:
    def create_wordcloud(text, stopwords, filename):
        wordcloud = \
        WordCloud(min_font_size...