Book Image

Julia 1.0 Programming - Second Edition

By : Ivo Balbaert
Book Image

Julia 1.0 Programming - Second Edition

By: Ivo Balbaert

Overview of this book

The release of Julia 1.0 is now ready to change the technical world by combining the high productivity and ease of use of Python and R with the lightning-fast speed of C++. Julia 1.0 programming gives you a head start in tackling your numerical and data problems. You will begin by learning how to set up a running Julia platform, before exploring its various built-in types. With the help of practical examples, this book walks you through two important collection types: arrays and matrices. In addition to this, you will be taken through how type conversions and promotions work. In the course of the book, you will be introduced to the homo-iconicity and metaprogramming concepts in Julia. You will understand how Julia provides different ways to interact with an operating system, as well as other languages, and then you'll discover what macros are. Once you have grasped the basics, you’ll study what makes Julia suitable for numerical and scientific computing, and learn about the features provided by Julia. By the end of this book, you will also have learned how to run external programs. This book covers all you need to know about Julia in order to leverage its high speed and efficiency for your applications.
Table of Contents (17 chapters)
Title Page
Copyright and Credits
Packt Upsell

Basic input and output

Julia's vision on input/output (I/O) is stream-oriented, that is, reading or writing streams of bytes. We will introduce different types of stream, file streams, in this chapter. Standard input (stdin) and standard output (stdout) are constants of the TTY type (an abbreviation for the old term, Teletype) that can be read from and written to in Julia code (refer to the code in Chapter 8\io.jl):

  • read(stdin, Char): This command waits for a character to be entered, and then returns that character; for example, when you type in J, this returns 'J'
  • write(stdout, "Julia"): This command types out Julia5 (the added 5 is the number of bytes in the output stream; it is not added if the command ends in a semicolon ;)

stdin and stdout are simply streams and can be replaced by any stream object in read/write commands. readbytes is used to read a number of bytes from a stream into a vector:

  • read(stdin,3): This command waits for an input, for example, abe reads three bytes from it, and...