1.1 Things you should know about R

• R is free & open-source.
• R is expert in data analysis & statistical computing.
• R is an interpreted, dynamically typed programming language, just like Python.
• Procedural programming is more common when using R - although R supports object-oriented programming.
• Strong supports from lots of user-created packages - ggplot2 for graphing, tidyverse for data manipulation...
• RStudio is an IDE for R which can make using R much easier.
• Rstudio does not come with a R software - you should install R first.

1.2 Installing R

brew install r

or download from a mirror: https://cran.r-project.org/mirrors.html

1.3 Installing RStudio

Free version: https://posit.co/downloads/

RStudio cheat sheet: https://ucdavis-bioinformatics-training.github.io/Oct2017-ILRI-Workshop/Cheat_Sheets/rstudio-IDE-cheatsheet.pdf

It is a good habit to create a new project for each different research problem. There are some important windows:

• Environment: Defined variables and functions.
• History: Commands history.
• Files: All files in the current working directory.