Book Image

Learning Julia

By : Anshul Joshi, Rahul Lakhanpal
Book Image

Learning Julia

By: Anshul Joshi, Rahul Lakhanpal

Overview of this book

Julia is a highly appropriate language for scientific computing, but it comes with all the required capabilities of a general-purpose language. It allows us to achieve C/Fortran-like performance while maintaining the concise syntax of a scripting language such as Python. It is perfect for building high-performance and concurrent applications. From the basics of its syntax to learning built-in object types, this book covers it all. This book shows you how to write effective functions, reduce code redundancies, and improve code reuse. It will be helpful for new programmers who are starting out with Julia to explore its wide and ever-growing package ecosystem and also for experienced developers/statisticians/data scientists who want to add Julia to their skill-set. The book presents the fundamentals of programming in Julia and in-depth informative examples, using a step-by-step approach. You will be taken through concepts and examples such as doing simple mathematical operations, creating loops, metaprogramming, functions, collections, multiple dispatch, and so on. By the end of the book, you will be able to apply your skills in Julia to create and explore applications of any domain.
Table of Contents (17 chapters)
Title Page
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
8
Data Visualization and Graphics

Vega


Vega is a data visualization library that provides a Julia wrapper around the Vega Visualization Grammar from Trifacta. It was created and developed by Randy Zwitch as an open source project.

Installing Vega is pretty simple to do, as listed in the METADATA.jl:

julia> Pkg.add("Vega")
julia> using Vega

However, Vega requires an internet connection to render all graphs because it does not store local copies of the JavaScript libraries. However, efforts are made to actually include all the JavaScript libraries as part of the package so that it does not require any internet connection in the future.

Vega provides a series of composite types, which are literally just the translation of Vega grammar in Julia. They help the end user to build visualizations in native Julia syntax. The following are all the primitives defined in Julia:

  • VegaVisualization
  • VegaData
  • VegaScale
  • VegaAxis
  • VegaLegend
  • VegaMark

Apart from these visualizations, Vega also provides interactivity to the graphs by providing some...