Objectives

Get to know Julia

Get a big-picture overview

Learn how to get started

Explore some core parts of the language

The Julia Programming Language

What is it?

https://julialang.org/

compiled (via LLVM)

complex and rational numbers

object-oriented and functional via multiple dispatch

dynamically-typed

parallel, async, multithreaded processing

implicit distribution capabilities

metaprogramming (code is data is code)

The Julia Programming Language

Julia distributed invocations

$ julia -p 2

julia> r = remotecall(rand, 2, 2, 2)
Future(2, 1, 4, nothing)

julia> s = @spawnat 2 1 .+ fetch(r)
Future(2, 1, 5, nothing)

julia> fetch(s)
2×2 Array{Float64,2}:
 1.18526  1.50912
 1.16296  1.60607

The Julia Programming Language

With some interesting metaprogramming support

julia> ex1 = Meta.parse("1 + 1")
:(1 + 1)

julia> dump(ex1)
Expr
  head: Symbol call
  args: Array{Any}((3,))
    1: Symbol +
    2: Int64 1
    3: Int64 1

julia> ex2 = Expr(:call, :+, 1, 1)
:(1 + 1)

julia> ex1 == ex2
true

julia> 

The Julia Programming Language

Hosting Julia in native code

#include <julia.h>
JULIA_DEFINE_FAST_TLS

int main(int argc, char *argv[])
{
    jl_init();

    /* run Julia commands */
    jl_eval_string("print(sqrt(2.0))");

    jl_atexit_hook(0);
    return 0;
}

$ gcc -o test -fPIC -I$JULIA_DIR/include/julia -L$JULIA_DIR/lib 
    -Wl,-rpath,$JULIA_DIR/lib test.c -ljulia

Getting Started with Julia

Installation

Homebrew (macOS, Linux): brew install julia

Chocolatey (Windows): choco install julia

Downloads: https://julialang.org/downloads/

Build from source: https://github.com/JuliaLang/julia

Getting Started with Julia

Hello, world

println("Hello, world!")

Run

julia hello.jl

Or run interactively

$ julia
               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.9.1 (2023-06-07)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> print("Hello world")
Hello world
julia> 

Getting Started with Julia

Some interesting CLI switches

--project=dir: Set dir as the home project/environment

-p/--procs: Launches N additional local worker processes

--machine-file file: Run processes on hosts listed in file

Summary

Julia is ...

a high-level language

... with some great performance characteristics

... and features to make it data-/scientific-friendly

Julia Resources

Books

Julia Resources

Websites

Credentials

Who is this guy?

Architect, Engineering Manager/Leader, "force multiplier"

http://www.newardassociates.com

http://blogs.newardassociates.com

Sr Distinguished Engineer, Capital One

Educative (http://educative.io) Author

Performance Management for Engineering Managers

Books

Developer Relations Activity Patterns (w/Woodruff, et al; APress, forthcoming)

Professional F# 2.0 (w/Erickson, et al; Wrox, 2010)

Effective Enterprise Java (Addison-Wesley, 2004)

SSCLI Essentials (w/Stutz, et al; OReilly, 2003)

Server-Based Java Programming (Manning, 2000)