Book Image

Julia 1.0 Programming Cookbook

By : Bogumił Kamiński, Przemysław Szufel
Book Image

Julia 1.0 Programming Cookbook

By: Bogumił Kamiński, Przemysław Szufel

Overview of this book

Julia, with its dynamic nature and high-performance, provides comparatively minimal time for the development of computational models with easy-to-maintain computational code. This book will be your solution-based guide as it will take you through different programming aspects with Julia. Starting with the new features of Julia 1.0, each recipe addresses a specific problem, providing a solution and explaining how it works. You will work with the powerful Julia tools and data structures along with the most popular Julia packages. You will learn to create vectors, handle variables, and work with functions. You will be introduced to various recipes for numerical computing, distributed computing, and achieving high performance. You will see how to optimize data science programs with parallel computing and memory allocation. We will look into more advanced concepts such as metaprogramming and functional programming. Finally, you will learn how to tackle issues while working with databases and data processing, and will learn about on data science problems, data modeling, data analysis, data manipulation, parallel processing, and cloud computing with Julia. By the end of the book, you will have acquired the skills to work more effectively with your data
Table of Contents (18 chapters)
Title Page
Copyright and Credits
Dedication
About Packt
Contributors
Preface
Index

Fetching data from the internet


In this recipe, we will show how to use Julia to obtain data from the internet, and how to extract information from web pages. We will write some sample code that extracts the number of stars from GitHub projects.

Getting ready

For this recipe, you need the following packages:HTTP.jl,Gumbo.jl, andCascadia.jl.These packages can simply be installed with the Julia package manager. In the Julia command line (REPL), simply press ] key and run the following commands:

(v1.0) pkg>addHTTP
(v1.0) pkg>addGumbo
(v1.0) pkg>addCascadia

 

This will install the aforementioned packages and all their dependencies.

Note

In the GitHub repository for this recipe, you will find the commands.txt file, which contains the presented sequence of Julia commands.

How to do it...

In this example, we will read the number of GitHub stars from a set of GitHub repositories present under the umbrella of the JuliaWeb organization:

  1. Start by loading the required modules as follows:
usingHTTP, Gumbo...