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
Title Page
Dedication
Contributors
Preface
Variables, Types, and Functions
Julia Workflow
Distributed Computing
Other Books You May Enjoy
Index

Ensuring type stability of your code

In this recipe, we discuss how to detect problems with the type stability of Julia code and how to solve them. In particular, we concentrate on exploring type stability in closures.

You will work with a function for calculating the roots of a quadratic equation:

using the well-known formula

if

.

Note

In the GitHub repository for this recipe, you will find the commands.txt file that contains the presented sequence of shell and Julia commands. Additionally, in the quad.jl file you can find the definitions of methods used in this recipe.

Now open your favorite terminal to execute the commands.

How to do it...

Start by running the command include("quad.jl"), which defines the following two functions for calculating the desired roots of the quadratic equation:

function quadratic1(a, b, c)
t(s) = (-b + s*sqrt(Δ))/(2a)
a == 0 && error("a must be different than zero")
Δ = Complex(b^2-4*a*c)
t(1), t(-1)
end

function quadratic2...