R Installation on Windows
Download R from here. Select a hosting site, for example,
we may select USA -> http://watson.nci.nih.gov/cran_mirror/ (National Cancer Institute, Bethesda, MD).
Next select "Download R for Windows". Click into "base", then click "Download R 2.xx.x for Windows". Save the file on your
computer, or you may start install by click "Run" button instead.
Click the downloaded file "R-2.xx.x-win.exe" to start installation. You may accept all default setting and click next all the way to finish the R installation. By default, there will be a R shortcut on the desktop after installation. The R can be started by clicking that icon.
The default working directory should be "C:/Users/xxx/Documents/". To check the working directory, type
getwd(). There are several methods to change the default working directory.
1. Open a random folder, click "Desktop" icon on the up left to open the desktop directory.
Right click the R shortcut icon, select "properties", change the "Start in" directory.
2. Add R to the PATH environment. Right click "My Computer" -> "Properties" -> "Advanced" -> "Environment variables", then append the R to the path. You now can start R from the windows shell.
You may use
setwd() to temporarily change the working directory.
R Installation on Linux
Download R from the same website. For example, for Redhat Enterprise Linux 5 (RHL5), Select "Download R for Linux" -> "redhat" -> "el5" -> "x86-64", and download the R-2.xx.x-xx.
Go to the downloaded file folder, type
rpm -ivh R-2.xx.
Since R has been maintained in the standard yum repos, you may install R by type
yum install R, or
yum update Rto get a recent version.
open .bashrc file under /root/, append the R bin path (add to .cshrc, if you use c shell):
export PATH=".:$PATH:/app/R-2.xx.x/bin". R can then be initiated from any directory by typing
R editors (recommended):
• Notepad++: Windows Only
• gedit: Redhat Linux Only
• RStudio: Powerful IDE, works on Windows, Mac and Linux
If you select "save Workspace image" during quit, all R objects will be written into a file ".RData" in the working directory, and all history command will be recorded into a file ".RHistory" in the working directory. By default, R will load all objects while starting. This may save time if you want to read a large file, but waste you time if you do not need the objects. You can delete the .RData and .Rhistory under the R working directory to delete all R objects and history commands.
Getting Help, for example function plot():
>?plot >help(plot) >??plot
Execute a R command file:
>source("test.R")Or under linux shell:
R CMD test.R
>sink("output.txt") #Divert output from console to file >sink() #Restores to the console output >objects() #Display current objects >ls() #Display current objects >rm(x) #Remove object x from R work space >getwd() #Display current work directory >data() #Display all built in datasets >install.packages("mmass") #Install package mmass >installed.packages() #Display all installed packages >ls("package:base") #List all functions of R Base
You may use the upward and downward arrow to recall and reexecute previous commands.