Book Image

Learning R Programming

By : Kun Ren
Book Image

Learning R Programming

By: Kun Ren

Overview of this book

R is a high-level functional language and one of the must-know tools for data science and statistics. Powerful but complex, R can be challenging for beginners and those unfamiliar with its unique behaviors. Learning R Programming is the solution - an easy and practical way to learn R and develop a broad and consistent understanding of the language. Through hands-on examples you'll discover powerful R tools, and R best practices that will give you a deeper understanding of working with data. You'll get to grips with R's data structures and data processing techniques, as well as the most popular R packages to boost your productivity from the offset. Start with the basics of R, then dive deep into the programming techniques and paradigms to make your R code excel. Advance quickly to a deeper understanding of R's behavior as you learn common tasks including data analysis, databases, web scraping, high performance computing, and writing documents. By the end of the book, you'll be a confident R programmer adept at solving problems with the right techniques.
Table of Contents (21 chapters)
Learning R Programming
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface

Array


An array is a natural extension to a matrix in its number of dimensions. More specifically, an array is a vector that is represented and accessible in a given number of dimensions (mostly more than two dimensions).

If you are already familiar with vectors and matrices, you won't be surprised to see how arrays behave.

Creating an array

To create an array, we call array() by supplying a vector of data, how this data is arranged in different dimensions, and sometimes the names of the rows and columns of these dimensions.

Suppose we have some data (10 integers from 0 to 9) and we need to arrange them in three dimensions: 1 for the first dimension, 5 for the second, and 2 for the third:

a1 <- array(c(0, 1, 2, 3, 4, 5, 6, 7, 8, 9), dim = c(1, 5, 2))
a1
## , , 1
## 
##     [,1] [,2] [,3] [,4] [,5]
## [1,]  0    1    2    3    4
## 
## , , 2
## 
##     [,1] [,2] [,3] [,4] [,5]
## [1,]  5    6    7    8    9

We can clearly see how we can access these entries by looking at the notations...