ESS - Emacs Speaks Statistics


1 General Information: README

This is the README file for the distribution of ESS version 18.10.3snapshot

ESS is a GNU Emacs package for interactive statistical programming and data analysis. Languages supported: the S family (S, S-PLUS and R), SAS, BUGS/JAGS and Stata. ESS grew out of the desire for bug fixes and extensions to S-mode and SAS-mode as well as a consistent union of their features in one package.

Installation instructions are provided in sections for both Unix and Windows; see below.

The current development team is led by Martin Maechler since August 2004. Former project leader A.J. (Tony) Rossini ( did the initial port to XEmacs and has been the primary coder. Martin Maechler ( and Kurt Hornik ( have assisted with the S family and XLispStat. Stephen Eglen ( has worked mostly on R support. Richard M. Heiberger ( has assisted with S/S-PLUS development for Windows. Richard and Rodney A. Sparapani ( have done much of the work improving SAS batch and interactive support. Rodney has also extended ESS to support BUGS/JAGS and has an interest in improving Stata support.

We are grateful to the previous developers of S-mode (Doug Bates, Ed Kademan, Frank Ritter, David M. Smith), SAS-mode (Tom Cook) and Stata-mode (Thomas Lumley).

1.1 License

The source and documentation of ESS is free software. You can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version.

ESS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License in the file COPYING in the same directory as this file for more details.

1.2 Installation

ESS supports GNU Emacs versions 25.1 and newer.

ESS is most likely to work with current/recent versions of the following statistical packages: R/S-PLUS, SAS, Stata, OpenBUGS and JAGS.

To build the PDF documentation, you will need a version of TeX Live or texinfo that includes texi2dvi.

There are two main methods used for installing ESS. You may install from a third-party repository or from source code. Once you install it, you must also activate or load ESS in each Emacs session, though installation from a third-party repository likely takes care of that for you. See Activating and Loading ESS for more details.

1.3 Installing from a third-party repository

ESS is packaged by many third party repositories. Many GNU/Linux distributions package it, usually with the name “emacs-ess” or similar.

ESS is also available through Milkypostman‚Äôs Emacs Lisp Package Archive (MELPA), a popular repository for Emacs packages. Instructions on how to do so are found on MELPA’s website. MELPA also hosts MELPA-stable with stable ESS builds. You may choose between MELPA with the latest and greatest features (and bugs) or MELPA-stable, which may lag a bit behind but should be more stable.

After installing, users should make sure ESS is activated or loaded in each Emacs session. See Activating and Loading ESS. Depending on install method, this may be taken care of automatically.

1.4 Installing from source

Stable versions of ESS are available at the ESS web page as a .tgz file or .zip file. ESS releases are GPG-signed, you should check the signature by downloading the accompanying .sig file and doing:

gpg --verify ess-18.10.tgz.sig

Alternatively, you may download the git repository. ESS is currently hosted on GitHub: git clone will download it to a new directory ESS in the current working directory.

We will refer to the location of the ESS source files as /path/to/ESS/ hereafter.

After installing, users should make sure they activate or load ESS in each Emacs session, see Activating and Loading ESS

Optionally, compile Elisp files, build the documentation, and the autoloads:

cd /path/to/ESS/

Without this step the documentation, reference card, and autoloads will not be available. Uncompiled ESS will also run slower.

Optionally, you may make ESS available to all users of a machine by installing it site-wide. To do so, run make install. You might need administrative privileges:

make install

The files are installed into /usr/share/emacs directory. For this step to run correctly on macOS, you will need to adjust the PREFIX path in Makeconf. The necessary code and instructions are commented in that file.

1.5 Activating and Loading ESS

After installing ESS, you must activate or load it each Emacs session. ESS can be autoloaded, and if you used a third-party repository (such as your Linux distribution or MELPA) to install, you can likely skip this section and proceed directly to Check Installation

Otherwise, you may need to add the path to ESS to load-path with:

(add-to-list 'load-path "/path/to/ESS/lisp")

You then need to decide whether to take advantage of deferred loading (which will result in a faster Emacs startup time) or require ESS when Emacs is loaded. To autoload ESS when needed (note that if installed from source, you must have run make):

(load "ess-autoloads")

To require ESS on startup, you can either put

(require 'ess-site)


(require 'ess-r-mode)

In your configuration file, depending on whether you want all ESS features or only R related features.

1.6 Check Installation

Restart Emacs and check that ESS was loaded from a correct location with M-x ess-version.

1.7 Starting an ESS process

To start an S session on Unix or on Windows when you use the Cygwin bash shell, simply type M-x S RET.

To start an S session on Windows when you use the MSDOS prompt shell, simply type M-x S+6-msdos RET.

1.8 Current Features

1.9 New Features

Changes and New Features in 19.04 (unreleased):

The following have been made obsolete or removed, see their documentation for more detail:

Bug Fixes in 18.10.3:

Bug Fixes in 18.10.2:

Bug Fixes in 18.10-1:

Changes and New Features in 18.10:

Many improvements to fontification:

Notable bug fixes:

Obsolete libraries, functions, and variables:

Changes and New Features in 17.11:

Changes and New Features in 16.10:

Bug fixes in 16.10:

Changes and New Features in 16.04:

Bug fixes in 16.04:

1.10 Reporting Bugs

Please send bug reports, suggestions etc. to, or post them on our github issue tracker

The easiest way to do this is within Emacs by typing

M-x ess-submit-bug-report

This also gives the maintainers valuable information about your installation which may help us to identify or even fix the bug.

If Emacs reports an error, backtraces can help us debug the problem. Type "M-x set-variable RET debug-on-error RET t RET". Then run the command that causes the error and you should see a *Backtrace* buffer containing debug information; send us that buffer.

Note that comments, suggestions, words of praise and large cash donations are also more than welcome.

1.11 Mailing Lists

There is a mailing list for discussions and announcements relating to ESS. Join the list by sending an e-mail with "subscribe ess-help" (or "help") in the body to; contributions to the list may be mailed to Rest assured, this is a fairly low-volume mailing list.

The purposes of the mailing list include

1.12 Authors