
			THE BASIC R README


	   (See "FAQ" and "RESOURCES" for more detailed information)
	   (See "INSTALL"             for help on installation)

1. INTRODUCTION

This directory contains the source code tree for R, which is a language
which is not entirely unlike (version 3 of) the S language developed at
AT&T Bell Laboratories by Rick Becker, John Chambers and Allan Wilks.

R is free software distributed under a GNU-style copyleft.

The core of R is an interpreted computer language with a syntax
superficially similar to C, but which is actually a "functional
programming language" with capabilities similar to Scheme. The language
allows branching and looping as well as modular programming using
functions. Most of the user-visible functions in R are written in R,
calling upon a smaller set of internal primitives. It is possible for
the user to interface to procedures written in C or Fortran languages
for efficiency, and also to write additional primitives.

The R distribution contains functionality for a large number of
statistical procedures. Among these are: linear and generalized linear
models, nonlinear regression models, time series analysis, classical
parametric and nonparametric tests, clustering and smoothing. There is
also a large set of functions which provide a flexible graphical
environment for creating various kinds of data presentations.

A package specification allows the production of loadable modules for
specific purposes, and several contributed packages are made available
through the CRAN sites (see RESOURCES).

2. HISTORY

R was initially written by Robert Gentleman and Ross Ihaka of the
Statistics Department of the University of Auckland.  In addition, a
large group of individuals has contributed to R by sending code and bug
reports.

Since mid-1997 there has been a core group who can modify the R source
code CVS archive.  The group currently consists of

	Douglas Bates, John Chambers, Peter Dalgaard, Robert Gentleman,
	Kurt Hornik, Ross Ihaka, Friedrich Leisch, Thomas Lumley, Martin
	Maechler, Guido Masarotto, Paul Murrell, Brian Ripley, Duncan
	Temple Lang and Luke Tierney.


3. PRESENT STATUS

The present version implements most of the functionality in the 1988
book "The New S Language" (the "Blue Book") and many of the
applications. In addition, we have implemented a large part of the
functionality from the 1992 book "Statistical Models in S" (the "White
Book").

All the R functions have been documented in the form of help pages in
an "output independent" form which can be used to create versions for
HTML, LaTeX, text etc.  A 800+ page Reference Index (a collection of
all the help pages) can be obtained in a variety of formats. The
manual `An Introduction to R' provides a more user-friendly starting
point, and there is an `R Language Definition' manual and more
specialized manuals on data import/export and extending R. See INSTALL
for instructions on how to generate these documents.


4. GOALS

Our aim at the start of this project was to demonstrate that it was
possible to produce an S-like environment which did not suffer from
the memory-demands and performance problems which S has.  Somewhat
later, we started to turn R into a "real" system, but unfortunately we
lost a large part of the efficiency advantage in the process, so have
recently revised the memory management mechanism and are looking for
other candidates for optimization.

Longer-term goals include to explore new ideas: e.g. virtual objects
and component-based programming, and expanding the scope of existing
ones like formula-based interfaces.  Further, we wish to get a handle
on a general approach to graphical user interfaces (preferably with
cross-platform portability), and to develop better 3-D and dynamic
graphics.


Sincerely,
The R Core Team.
