Book Image

Spark for Data Science

By : Srinivas Duvvuri, Bikramaditya Singhal
Book Image

Spark for Data Science

By: Srinivas Duvvuri, Bikramaditya Singhal

Overview of this book

This is the era of Big Data. The words ‘Big Data’ implies big innovation and enables a competitive advantage for businesses. Apache Spark was designed to perform Big Data analytics at scale, and so Spark is equipped with the necessary algorithms and supports multiple programming languages. Whether you are a technologist, a data scientist, or a beginner to Big Data analytics, this book will provide you with all the skills necessary to perform statistical data analysis, data visualization, predictive modeling, and build scalable data products or solutions using Python, Scala, and R. With ample case studies and real-world examples, Spark for Data Science will help you ensure the successful execution of your data science projects.
Table of Contents (18 chapters)
Spark for Data Science
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Preface

Singular Value Decomposition


The Singular Value Decomposition (SVD) is one of the centerpieces of linear algebra and is widely used for many real-world modeling requirements. It provides a convenient way of breaking a matrix into simpler, smaller matrices. This leads to a low-dimensional representation of a high-dimensional matrix. It helps us eliminate less important parts of the matrix to produce an approximate representation. This technique is useful in dimensionality reduction and data compression.

Let M be a matrix of size m-rows and n-columns. The rank of a matrix is the number of rows that are linearly independent. A row is considered independent if it has at least one non-zero element and it is not a linear combination of one or more rows. The same rank will be obtained if we considered columns instead of rows - as in linear algebra.

If the elements of one row are the sum of two rows, then that row is not independent. Then as a result of SVD, we find three matrices, U, , and V that...