Book Image

Julia Programming Projects

By : Adrian Salceanu
Book Image

Julia Programming Projects

By: Adrian Salceanu

Overview of this book

Julia is a new programming language that offers a unique combination of performance and productivity. Its powerful features, friendly syntax, and speed are attracting a growing number of adopters from Python, R, and Matlab, effectively raising the bar for modern general and scientific computing. After six years in the making, Julia has reached version 1.0. Now is the perfect time to learn it, due to its large-scale adoption across a wide range of domains, including fintech, biotech, education, and AI. Beginning with an introduction to the language, Julia Programming Projects goes on to illustrate how to analyze the Iris dataset using DataFrames. You will explore functions and the type system, methods, and multiple dispatch while building a web scraper and a web app. Next, you'll delve into machine learning, where you'll build a books recommender system. You will also see how to apply unsupervised machine learning to perform clustering on the San Francisco business database. After metaprogramming, the final chapters will discuss dates and time, time series analysis, visualization, and forecasting. We'll close with package development, documenting, testing and benchmarking. By the end of the book, you will have gained the practical knowledge to build real-world applications in Julia.
Table of Contents (19 chapters)
Title Page
Copyright and Credits
About Packt

Regular expressions

Regular expressions are used for powerful pattern-matching of substrings within strings. They can be used to search for a substring in a string, based on patterns—and then to extract or replace the matches. Julia provides support for Perl-compatible regular expressions.

The most common way to input regular expressions is by using the so-called nonstandard string literals. These look like regular double-quoted strings, but carry a special prefix. In the case of regular expressions, this prefix is "r". The prefix provides for a different behavior, compared to a normal string literal.

For example, in order to define a regular string that matches all the letters, we can use r"[a-zA-Z]*".

Julia provides quite a few nonstandard string literals—and we can even define our own if we want to. The most widely used are for regular expressions (r"..."), byte array literals (b"..."), version number literals (v"..."), and package management commands (pkg"...").

Here is how we build a regular...