This document provides an introduction to R, including what R is, how to install and use it, common mistakes, and data structures. It discusses that R was created by Ross Ihaka and Robert Gentleman and contains over 10,000 user-developed packages on topics like statistics, graphics, and data analysis. It also provides instructions on installing R from its homepage or a Italian download site, using the R console and R Studio interfaces, the workspace environment, and saving workspaces to preserve data between sessions.

1. Introduction to R
Dott.ssa Paola Pozzolo
sos.unistat@gmail.com
Asti, 24/06/2019

2. R developers: Ross Ihaka and Robert Gentleman

4. What is ?

5. Why don’t everybody use ?
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7. R Packages
The «base» R system contains the base package,
which contains the most fundamental functions.
Over 10,000 other packages are available on CRAN
developed by users and programmers around the world.

8. Installing R
• R Homepage: http://www.r-project.org/
• CRAN for Italian download: https://cran.stat.unipd.it/

9. R Console

10. R Studio

11. Working with R
• R is a case-sensitive language (mydata differ from Mydata)
• Commands are entered interactively at the R user prompt. Up and
down arrow keys scroll through your command history.
• Objects are assigned values using : object <- function(par1, par2, …)
• If you specify a new value for an object again, R will forget what value
it had before.
• Comments are preceded by the # symbol

12. Common mistakes in R programming

13. Data operators

14. Data analysis in R: an example

15. R data structures

16. The workspace
It is your current R working
environment and includes any
user-defined objects (vectors,
matrices, data frames, lists,
functions).

17. R Reference Card https://cran.r-project.org/doc/contrib/Short-refcard.pdf

18. R Commander

19. How to install R Commander?
 Write in R console:
install.packages("Rcmdr", dependencies=TRUE)
OR
 From the menu: Packages | Install package…  Rcmdr
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How to load R Commander?
 From the menu: Packages Load packages  Rcmdr
OR
 Write in R console:
library(Rcmdr)
If you accidently close the Rcmdr window, type Commander() in the R Console and hit OK

20. R Commander interface
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Script window
shows most
recent commands
or code
Output window
shows results
from most recent
commands
Message window
reports errors
from commands
Menu system has
many commonly
used diagnostics
and tests

21. When you quit R …
Save R workspace in order to save your data in the R format.
Save also your output and your commands. It’s essential if you want to re-run the analyses later.
R have no knowledge of previous packages loaded: load the package at the start of each R session .
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22. How to save?
iii. Save R workspace: R will save 2 files: .Rdata and .Rhistory

23. Now it’s your turn...
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E-mail me at sos.unistat@gmail.com