r - Man Page

Provides hash-bang (#!) capability for R (www.r-project.org)

Examples (TL;DR)

Synopsis

r [options] [-|file] [R arguments]

Description

Launches GNU R to execute the specified file containing R commands, or takes commands from stdin if '-' is used to denote stdin, using the specified options. This makes it suitable to create R scripts via the so-called shebang '#!/' line. The optional R arguments are stored in the  R vector argv.

Options

-h,  --help

Display a short help list.

--usage

Give a short usage message.

-V,  --version

Show the version number.

-v,  --vanilla

Pass the '--vanilla' option to R.

-t,  --rtemp

Use a per-session temporary directory as R does.

-i,  --interactive

Force 'interactive()' to evaluate to TRUE, whereas the default is FALSE.

-q,  --quick

Skip autoload (i.e. delayed assign) of default libraries.

-p,  --verbose

Print the value of expressions to the console.

-l,  --packages list

Load the R packages from the comma-separated 'list'.

-d,  --datastdin

Evaluates 'X <- read.csv(file="stdin", stringsAsFactors=FALSE)' to read a data set from stdin.

-L,  --libpath dir

Add directory to library path via '.libPaths(dir)'.

-e, --eval expr

Evaluate 'expr' in R.

Usage

r can be used in command-line 'pipes' as well as in 'shebang'-style scripts.

Examples

Piping R commands:

echo 'cat(pi^2,"\n")' | r

Equivalently, R commands can be given on the command-line:

r -e 'cat(pi^2, "\n")'

Alternatively, commands can be stored in a file, which in turn might use R command 'readLines' to process stdin input:

$ cat examples/fsizes.r
fsizes <- as.integer(readLines())
print(summary(fsizes))
stem(fsizes)

which can be evaluated by r with the following command:

ls -l /boot | awk '!/^total/ {print $5}' | r examples/fsizes.r

The script file may contain a "shebang" line:

$ cat examples/install.r
#!/usr/bin/env r
# a simple example to install one or more packages
if (is.null(argv) | length(argv)<1) {
  cat("Usage: installr.r pkg1 [pkg2 pkg3 ...]0)
  q()
}
repos <- "http://cran.us.r-project.org"
lib.loc <- "/usr/local/lib/R/site-library"
install.packages(argv, lib.loc, repos, dependencies=TRUE)

and if it is executable, it can be called as:

examples/install.r "TeachingDemos"

See the examples directory in the sources for more.

Note

The executable program is called  r, but the project is called littler to avoid confusion with the real GNU R.

See Also

The  GNU R language is documented extensively at the R website (http://www.r-project.org) and in several manuals available in html, info and pdf.

Authors

Jeffrey Horner <jeff.horner@vanderbilt.edu>. Dirk Eddelbuettel <edd@debian.org>.

Info

September 2006