R

Installing R and RStudio

Step 1: Install R

R is the underlying statistical computing environment and must be installed before RStudio.

1. Navigate to the official CRAN repository: https://cran.r-project.org
2. Select the installer appropriate for your operating system:
   • Windows: Click Download R for Windows → base → download and execute the installer
   • macOS: Click Download R for macOS → select the build matching your architecture (Apple Silicon users should select the arm64 build)
   • Linux: Follow the distribution-specific installation instructions provided on the page
3. Run the installer using the default configuration settings.

Step 2: Install RStudio Desktop

RStudio is an integrated development environment (IDE) for R. It requires a prior R installation to function.

1. Navigate to: https://posit.co/download/rstudio-desktop/
2. Download the free RStudio Desktop release for your operating system
3. Execute the installer and follow the on-screen instructions
4. Upon launching RStudio, the application should automatically detect the installed R environment

Important: R and RStudio are distinct pieces of software. RStudio does not bundle R; it serves solely as an interface to an existing R installation.

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Authoring Documents with R Markdown and Generating PDF Output

R Markdown is a document format that integrates prose, code, and computational output within a single reproducible file. The following steps outline the process of creating an R Markdown document and rendering it as a PDF.

Step 1: Install Required Packages

Execute the following commands in the RStudio Console:

install.packages("rmarkdown")
install.packages("knitr")

Step 2: Install a LaTeX Distribution

PDF rendering requires a LaTeX engine. The tinytex package provides a lightweight, self-contained LaTeX distribution suitable for most use cases:

install.packages("tinytex")
tinytex::install_tinytex()

Restart RStudio after installation to ensure the LaTeX binaries are correctly registered.

Step 3: Create a New R Markdown File

1. From the RStudio menu, select: File → New File → R Markdown…
2. Specify a title and author in the dialogue box; set the default output format to PDF
3. Click OK to generate the template file

Step 4: Configure the YAML Header

Every R Markdown document begins with a YAML front matter block delimited by ---. This block controls document metadata and output settings:

---
title: "Assignment Title"
author: "Full Name (Student ID)"
date: "2024-01-01"
output: pdf_document
---

Step 5: Write Document Content

R Markdown uses standard Markdown syntax for formatting prose, supplemented by fenced code chunks for embedding R code:

Syntax	Rendered Output
# Heading 1	First-level heading
## Heading 2	Second-level heading
**bold**	bold
*italic*	italic
Fenced code block with {r}	Executed R code with output

Example code chunk:

summary(mtcars)

      mpg             cyl             disp             hp       
 Min.   :10.40   Min.   :4.000   Min.   : 71.1   Min.   : 52.0  
 1st Qu.:15.43   1st Qu.:4.000   1st Qu.:120.8   1st Qu.: 96.5  
 Median :19.20   Median :6.000   Median :196.3   Median :123.0  
 Mean   :20.09   Mean   :6.188   Mean   :230.7   Mean   :146.7  
 3rd Qu.:22.80   3rd Qu.:8.000   3rd Qu.:326.0   3rd Qu.:180.0  
 Max.   :33.90   Max.   :8.000   Max.   :472.0   Max.   :335.0  
      drat             wt             qsec             vs        
 Min.   :2.760   Min.   :1.513   Min.   :14.50   Min.   :0.0000  
 1st Qu.:3.080   1st Qu.:2.581   1st Qu.:16.89   1st Qu.:0.0000  
 Median :3.695   Median :3.325   Median :17.71   Median :0.0000  
 Mean   :3.597   Mean   :3.217   Mean   :17.85   Mean   :0.4375  
 3rd Qu.:3.920   3rd Qu.:3.610   3rd Qu.:18.90   3rd Qu.:1.0000  
 Max.   :4.930   Max.   :5.424   Max.   :22.90   Max.   :1.0000  
       am              gear            carb      
 Min.   :0.0000   Min.   :3.000   Min.   :1.000  
 1st Qu.:0.0000   1st Qu.:3.000   1st Qu.:2.000  
 Median :0.0000   Median :4.000   Median :2.000  
 Mean   :0.4062   Mean   :3.688   Mean   :2.812  
 3rd Qu.:1.0000   3rd Qu.:4.000   3rd Qu.:4.000  
 Max.   :1.0000   Max.   :5.000   Max.   :8.000  

Step 6: Render to PDF

Click the Knit button in the RStudio toolbar, or use the keyboard shortcut Ctrl+Shift+K (Windows/Linux) or Cmd+Shift+K (macOS), and select Knit to PDF.

Note on CJK character rendering: If Chinese, Japanese, or Korean characters appear as missing glyphs in the PDF output, specify an alternative LaTeX engine in the YAML header:

output:
  pdf_document:
    latex_engine: xelatex
header-includes:
  - \usepackage{fontspec}
  - \setmainfont{Noto Sans CJK TC}

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