Book Image

Mastering Julia - Second Edition

By : Malcolm Sherrington
Book Image

Mastering Julia - Second Edition

By: Malcolm Sherrington

Overview of this book

Julia is a well-constructed programming language which was designed for fast execution speed by using just-in-time LLVM compilation techniques, thus eliminating the classic problem of performing analysis in one language and translating it for performance in a second. This book is a primer on Julia’s approach to a wide variety of topics such as scientific computing, statistics, machine learning, simulation, graphics, and distributed computing. Starting off with a refresher on installing and running Julia on different platforms, you’ll quickly get to grips with the core concepts and delve into a discussion on how to use Julia with various code editors and interactive development environments (IDEs). As you progress, you’ll see how data works through simple statistics and analytics and discover Julia's speed, its real strength, which makes it particularly useful in highly intensive computing tasks. You’ll also and observe how Julia can cooperate with external processes to enhance graphics and data visualization. Finally, you will explore metaprogramming and learn how it adds great power to the language and establish networking and distributed computing with Julia. By the end of this book, you’ll be confident in using Julia as part of your existing skill set.
Table of Contents (14 chapters)

Multidimensional vectors and computing pi (revisited)

We will start by defining a vector in three dimensions; this is a vector in the mechanical sense and not the Julia vector sense, that is, a one-dimensional array.

We will define a V3D module using the following code:

#=
  This module uses Float64 components but could use a
  parameterised type {T} as will be seen later
=#
module V3D
# import operators from Base and Linear Algebra
import Base: +, *, /, ==, <, >, zero, one, iszero
import LinearAlgebra: norm, dot
# and export the type Vec3 and norm, dist functions (for Vec3)
export Vec3, norm, dist
# define a simple structure to hold the coordinates of the vector
struct Vec3
  x::Float64
  y::Float64
  z::Float64
end
# and the 'usual' runs for manipulating vectors
(+)(a::Vec3, b::Vec3) = Vec3(a.x+b.x, a.y+b.y, a.z+b.z)
(*)(p::Vec3, s::Real) = Vec3(p.x*s, p.y*s, p.z*s)
(*)(s::Real, p::Vec3) = p*s
(/)(p::Vec3, s...