.TH R 1
.SH NAME
R \- a language for data analysis and graphics
.SH SYNOPSIS
.B R
[
.I options
]
[
<
.I infile
]
[
> 
.I outfile
]
.SH DESCRIPTION
R is a language which bears a passing resemblance to the S language
developed at AT&T Bell Laboratories.
It provides support for a variety of statistical and graphical analyses.
R is a true computer language which contains a number
of control-flow constructions for iteration and alternation.
It allows users to add additional functionality by defining
new functions.
.LP
On platforms which support the
.BR dlopen (3)
interface, Fortran and C code can be linked and called at run time.
.LP
On systems which have the GNU
.BR readline (3)
library, R will maintain a command history,
so that commands can be recalled, edited and
re-executed.
.SH OPTIONS
The following options allow users to change the amount of memory
which R uses to store its internal data sets.
If possible these sizes should be set so that R does not use
more than the amount of physical memory available on the machine
where the program is executing.
This will minimize paging and ensure that execution
is as efficient as possible.
.TP
\fB\-v\fP \fIn\fP
Use a vector heap of size \fIn\fP megabytes (the default is 2).
.TP
\fB\-n\fP \fIn\fP
The number of \fIcons cells\fP (each occupying 16 bytes)
which R is to use (the default is 200000).
.LP
The following options relate to the saving and restoring of a user's
data sets and functions at startup and termination.
.TP
.B \-nosave
Do not save the data sets at the end of the R session.
This is only effective when R is used non-interactively.
.TP
.B \-save
Do save data sets.
.TP
.B \-norestore
Do not restore any previously saved datasets (an \fIimage\fP).
.TP
.B \-restore
Do restore previously saved datasets (this is the default).
.LP
The following options are present to support the use of
R from other programs.  In particular, the
.B \-noreadline
option exists so that R can be run under
.IR emacs (1)
and
.IR xemacs (1)
using ESS.
.TP
.B \-noreadline
Turn off the use of the
.IR readline (3)
command line editing.
.TP
.B \-quiet
Make R run as quietly as possible.  This option is intended
to support programs which use R to compute results for them.
.LP
These options are available so that the R developers can
carry debugging.
.TP
.B \-xxgdb
run R under the control of the
.IR xxgdb (1)
debugger.
.TP
.B \-gdb
run R under the control of the
.IR gdb (1)
debugger.
.SH STARTUP PROCESSING
When R is invoked it searches for the files
.B .Rprofile
and
.B ~/.Rprofile
(in that order) and executes any statements
in the first of these files to be found.
Finally, if a user has defined a function called
.BR \&.First ,
it will be invoked.
After these steps, an read-eval-print loop is run
for user input.
.SH FILES
.PD 0
.TP 12
\&.RData
saved data sets.
.TP
\&.Rhistory
saved command history.
.TP
\&.Rprofile
current directory startup file.
.TP
\&~/.Rprofile
home directory startup file.
.PD
.SH SEE ALSO
.BR S (1) ,
.BR Splus (1),
.BR readline (3).
.SH BUGS
R is very close to S in both syntax and semantics, but is not identical.
Whether this is a bug of feature is an open question.