RStudio is an Integrated Development Environment (IDE) for R it helps you:

• write code - makes suggestions
• view the output of your code, including plots
• find errors
• manage files
• View documentation

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RStudio used to be the name of a company that is now called Posit.

First it is important to be familiar with the layout. When you first open RStudio, you will see 3 panes.

To save a copy of your code. You must open a file first - this will open a 4th pane. These files include Scripts or what are called R Markdown files.

You will see a popup that you can just say “OK” to for now.

Nice! now we have a place to save code! This is where we will mostly be working.

1. The Source/Editor:
   • Static copy of what you did (reproducibility)
   • Top by default
   • saves your code
2. The R Console:
   • Calculator
   • Try things out interactively, then add to your editor
   • Bottom by default
   • doesn’t save your code

Super useful “cheatsheet”: LINK

It will look like this with text in it.

Although people will use scripts often, and they are good for more programmatic purposes, we generally don’t recommend them for Public Health Researchers.

For data analyses, R Markdown files are generally superior because they allow you to check your code and write more info about your code.

• Tells you what objects are in R
• What exists in memory/what is loaded?/what did I read in?

History

• Shows previous commands. Good to look at for debugging, but don’t rely on it.
  Instead use RMarkdown!
• Also type the “up” key in the Console to scroll through previous commands

• Files - shows the files on your computer of the directory you are working in
• Help - shows help of R commands
• Plots - pictures and figures

If RStudio doesn’t look the way you want (or like our RStudio), then:

Click on the pane button, which looks like a waffle with 4 indentations. Scroll down to “Pane Layout”.

R Markdown files (.Rmd) help generate reports that include your code and output.

1. Helps you describe your code
2. Allows you to check the output
3. Can create many different file types

Within R Markdown files are code “chunks”.

This is where you can type R code and run it!

Clicking the run (play) button runs the code in the chunk.

Ctrl + Enter on Windows or Command + Enter on Mac in your script evaluates that line of code

• generally see a preview of the output of the code just below the chunk
• see the code in the console