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


We've seen ranges a bit earlier, when learning to index into strings. They can be as simple as the following:

julia> r = 1:20 

As with previous collections, we can index into ranges:

julia> abc = 'a':'z' 
julia> abc[10] 
'j': ASCII/Unicode U+006a (category Ll: Letter, lowercase) 
julia> abc[end] 
'z': ASCII/Unicode U+007a (category Ll: Letter, lowercase)

A range can be expanded into its corresponding values by using the splat operator, "...". For example, we can splat it into a tuple:

julia> (1:20...,) 
(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20) 







We can also splat it into a list:

julia> [1:20...] 
20-element Array{Int64,1}


The same is true for Tuples, which can also be splatted into lists, among other things: [(1,2,3)...].

We can see that the range steps in increments of one, by default. We can change that by passing it an optional step parameter. Here is an example of a range between 0 and 20 with a step of...