Book Image

Learning Jupyter

By : Dan Toomey
Book Image

Learning Jupyter

By: Dan Toomey

Overview of this book

Jupyter Notebook is a web-based environment that enables interactive computing in notebook documents. It allows you to create and share documents that contain live code, equations, visualizations, and explanatory text. The Jupyter Notebook system is extensively used in domains such as data cleaning and transformation, numerical simulation, statistical modeling, machine learning, and much more. This book starts with a detailed overview of the Jupyter Notebook system and its installation in different environments. Next we’ll help you will learn to integrate Jupyter system with different programming languages such as R, Python, JavaScript, and Julia and explore the various versions and packages that are compatible with the Notebook system. Moving ahead, you master interactive widgets, namespaces, and working with Jupyter in a multiuser mode. Towards the end, you will use Jupyter with a big data set and will apply all the functionalities learned throughout the book.
Table of Contents (16 chapters)
Learning Jupyter
About the Author
About the Reviewer

Our first Spark script

Our first script reads in a text file and sees how much the line lengths add up to:

import pyspark
if not 'sc' in globals():
    sc = pyspark.SparkContext()
lines = sc.textFile("Spark File Words.ipynb")
lineLengths = s: len(s))
totalLength = lineLengths.reduce(lambda a, b: a + b) 

In the script, we are first initializing Spark-only if we have not done already. Spark will complain if you try to initialize it more than once, so all Spark scripts should have this if prefix statement.

The script reads in a text file (the source of this script), takes every line, and computes its length; then it adds all the lengths together.

A lambda function is an anonymous (not named) function that takes arguments and returns a value. In the first case, given a string s, it returns its length.

A reduce function takes an argument, applies the second argument to it, replaces the first value with the result, and then proceeds with the rest of the list. In...