The R Project SVN R

            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, 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 1998
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 700+ page Reference Index (a collection of
all the help pages) can be obtained in a variety of formats. The
document "An Introduction to R" provides a more user-friendly starting
point. 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
seem to have lost a large part of the efficiency advantage in the
process, so one of our short-term goals is to revise the memory
management mechanism and look 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.