2 Introduction to R

This workshop is beginner-level introduction to programming in R. The course is designed to be taught in two sessions of 3 hours each and is focused on the application of R to the analysis of tabular data from clinical trials.

2.1 R Markdown File

R Markdown files act as notebooks which can make it easier to document and share code. All the results from the code as well as your comments and descriptions can be combined into one, tidy document. This makes it easy to combine insights, protocols and figures in a practical and organized fashion.

2.2 Learning objectives

• Basic Operations in R

• R Markdown vs. R Script

• RStudio IDE

2.3 Comments

Comments are embedded into your code to help explain its purpose. This is extremely important for reproducibility and for documentation.

# This is a comment line 
# print('hello world')

2.4 Syntax

2.5 Creating variables

# The convention is to use left hand assignation 
var1 <- 12
var2 <- "hello world"

2.6 Printing Variables

var1

## [1] 12

var2

## [1] "hello world"

print(var1)

## [1] 12

print(var2)

## [1] "hello world"

# It is also possible to use the '=' sign, but is NOT a good practice
var1 = 13
var2 = "hello world"
var1

## [1] 13

var2

## [1] "hello world"

rm("var1")