AN INTRODUCTION TO R
are illustrated by practical examples and it is our hope that this will enable readers to get started without too many problems.
1.2 Installing R
The R system for statistical computing consists of two major parts: the base system and a collection of user contributed add-on packages. The R language is implemented in the base system. Implementations of statistical and graphical procedures are separated from the base system and are organised in the form of packages. A package is a collection of functions, examples and documen- tation. The functionality of a package is often focused on a special statistical methodology. Both the base system and packages are distributed via the Com- prehensive R Archive Network (CRAN) accessible under
1.2.1 The Base System and the First Steps
The base system is available in source form and in precompiled form for various Unix systems, Windows platforms and Mac OS X. For the data analyst, it is sufficient to download the precompiled binary distribution and install it locally. Windows users follow the link
download the corresponding file (currently named rw3012.exe), execute it locally and follow the instructions given by the installer.
Depending on the operating system, R can be started either by typing ‘R’ on the shell (Unix systems) or by clicking on the R symbol (as shown left) created by the installer (Windows). R comes without any frills and on start up shows simply a short introductory message including the version number and
a prompt ‘>’:
R : Copyright 2014 The R Foundation for Statistical Computing Version 3.1.2 (2014-10-31), ISBN 3-900051-07-0
R is free software and comes with ABSOLUTELY NO WARRANTY. You are welcome to redistribute it under certain conditions. Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors. Type 'contributors()' for more information and 'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or 'help.start()' for an HTML browser interface to help. Type 'q()' to quit R.
One can change the appearance of the prompt by
options(prompt = "R> ")