The R Project SVN R

R for Windows FAQ
Frequently Asked Questions on R for Windows
Version for rw1010
Brian Ripley


Table of Contents
*****************


1 Introduction

2 Installation and Usage
  2.1 Where can I find the latest version?
  2.2 How do I install R for Windows?
  2.3 How do I run it?
  2.4 How can I keep workspaces for different projects in different directories?
  2.5 How do I print from R?
  2.6 Can I use `R BATCH'?
  2.7 Can I use rwXxxx with ESS and emacs?
  2.8 What are HOME and working directories?

3 Packages
  3.1 Can I install packages (libraries) in this version?
  3.2 I don't have permission to write to the `rwXxxx/library' directory.
  3.3 The packages I installed do not appear in the HTML help system.
  3.4 My functions are not found by the HTML help search system.

4 Windows Features
  4.1 What should I expect to behave differently from the Unix version of R?
  4.2 I hear about some nifty features: please tell me about them!

5 Workspaces
  5.1 My workspace gets saved in a strange place: how do I stop this?
  5.2 How do I store my workspace in a different place?
  5.3 Can I load workspaces saved under Unix/GNU-Linux?

6 The R Console and Fonts
  6.1 I would like to be able to use Japanese fonts
  6.2 I don't see characters with accents at the R console, for example in ?text.
  6.3 When using Rgui the output to the console seems to be delayed.
  6.4 Long lines in the console or pager are truncated.

7 Building from Source
  7.1 How can I compile R from source?
  7.2 How do I debug code that I have compiled and dyn.load-ed?
  7.3 How do I include C++ code?
  7.4 The output from my C code disappears. Why?
  7.5 The output from my Fortran code disappears. Why?




1 Introduction
**************

This FAQ is for the Windows port of R: it describes features specific to
that version. The main R FAQ can be found at

     `http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html'.

The information here applies only to recent versions of R for Windows,
(`rw1000' or later); the current version is often called something like
`rw1010' (although not officially).


2 Installation and Usage
************************

2.1 Where can I find the latest version?
========================================

Go to any CRAN site (see `http://cran.r-project.org/mirrors.html' for a
list), navigate to the `bin/windows/windows-NT/base' directory and
collect the files you need. You will need at least the files

           rwXxxxb1.zip rwXxxxb2.zip
           rwXxxxh.zip (text help) or rwXxxxch.zip (Compiled HTML help)

and you may want `rwXxxxwh.zip' (the Windows help files) or
`rwXxxxw.zip' (the HTML format help files), `rwXxxxl.zip' (the LaTeX
format help files, used for offline printing), or `rwXxxxd?.zip' (the
draft manuals, in PDF).

Optionally, you can download the installer, `rwinst.exe'.

2.2 How do I install R for Windows?
===================================

First, you need Windows 95 or 98 or NT4 or 2000: Windows 3.11+win32s
will not work. Your file system must allow long file names (as is
likely except perhaps for some network-mounted systems).

The simplest way is to run the installer (double-click on the icon for
`rwinst.exe' and navigate its wizard-like pages).  Alternatively, choose
a location and unzip the zip files (with a tool that preserves long
file names and the directory structure: we recommend the INFO-ZIP
project's `unzip'). All the files will unpack into a directory called
`rwXxxx', for some `Xxxx'.

Choose a working directory for R. Make a shortcut to
`rwXxxx\bin\Rgui.exe' on your desktop or somewhere on the Start menu
file tree. Right-click the shortcut, select Properties... and change
the `Start in' field to your working directory.

You may also want to add command-line arguments at the end of the
Target field. We use `--vsize=10M --nsize=400k'. You can also set
environment variables at the end of the Target field, for example
`R_LIBS=e:/R/library'.

2.3 How do I run it?
====================

Just double-click on the shortcut you prepared at installation.

If you want to set up another project, make a new shortcut or use the
existing one, and change the `Start in' field of the Properties.

2.4 How can I keep workspaces for different projects in different directories?
==============================================================================

Create a separate shortcut for each project: see Q2.3. All the paths to
files used by R are relative to the starting directory, so setting the
`Start in' field automatically helps separate projects.

2.5 How do I print from R?
==========================

It depends what you want to print.

   * You can print the graphics window from its menu or by using
     `dev.print()'.

   * You can print from the R console or pager by `File | Print'.

   * You can print help files from the pager or HTML browser.

   * If you have configured `RHOME\bin\helpPRINT.bat' and have latex
     installed you can print help files by `help(fn_name,
     offline=TRUE)'.

2.6 Can I use `R BATCH'?
========================

No, but you can set up a batch file using `rterm.exe'. A sample batch
file might contain (as one line)

     path_to_R\bin\rterm.exe --vsize=10M --nsize=500k --no-restore --no-save < %1 > %1.out

2.7 Can I use rwXxxx with ESS and emacs?
========================================

Yes. The latest versions of ESS (e.g. 5.1.13) come with support for this
version of R, and there is support for interrupting the R process from
ESS (by `C-c C-c').

For help with ESS, please send email to `ESS-help@stat.ethz.ch', not
the R mailing lists.

2.8 What are HOME and working directories?
==========================================

Several places in the documentation use these terms.

The working directory is the directory from which `Rgui' or `Rterm' was
launched, unless a shortcut was used when it is given by the `Start in'
field of the shortcut's properties. You can find this from R code by
the call `getwd()'.

The home directory is set as follows:
If environment variable `R_USER' is set, its value is used.
Otherwise if environment variable `HOME' is set, its value is used.
Otherwise if environment variables `HOMEDRIVE' and `HOMEPATH' are set,
the value is `${HOMEDRIVE}${HOMEPATH}'.
If all of these fail, the current working directory is used.

You can find this from R code by `getenv("R_USER")'.


3 Packages
**********

3.1 Can I install packages (libraries) in this version?
=======================================================

Yes, of course. The easy way is to see if a pre-compiled binary version
of the package is available: look on CRAN at
`bin/windows/windows-NT/contrib'. If there is, download the zip file
and unpack it in the `rwXxxx\library' directory, using `unzip' or
similar, or using the installer `rwinst.exe'.  Perhaps even easier is
to use the R function `install.packages()': check out its help page.

If there is not a binary version or that is not up-to-date or you prefer
compiling from source, get `rwXxxxsp.zip' from the distribution (see
Q1.1) and unpack it in `rwXxxx'. Then `cd src\gnuwin32' and read
`README.packages'. You will need to collect and install several tools
to use this. Once you have done so, installation is easy: just run
`make pkg-pkgname'. To check the package (run all the examples on its
help pages) use `make pkgcheck-pkgname'.

3.2 I don't have permission to write to the `rwXxxx/library' directory.
=======================================================================

You can install packages anywhere and use the environment variable
`R_LIBS' to point to the library location(s). You can also set the R
variable `.lib.loc' in your `.Rprofile' or when running R.

Suppose your packages are installed in `p:\mylibs'. Then you can EITHER

     set R_LIBS to p:\mylibs

OR put in the `.Rprofile' in the working directory or your home
directory

     .lib.loc <- c("p:/mylibs", .Library)

OR use a package by, e.g.

     library(MASS, lib.loc="p:/mylibs")

How you set an environment variable is system specific: in Windows 9x
you can set them in autoexec.bat or in an MS-DOS window from which you
launch `Rgui' / `Rterm'. Under Windows NT/2000 you can use the control
panel or the properties of `My Computer'. You can also set them on the
command line, for example in the shortcut you could have

     path_to_R\bin\rgui.exe --vsize=10M R_LIBS=e:/R/library

and you can set variables in a file `.Renviron' in the working directory
or your home directory, for example

     R_LIBS=e:/R/library
     R_VSIZE=10M
     R_NSIZE=400k

The order of precedence is the command line (flags before variables)
then `.Renviron' then the inherited environment.

You can also build packages from anywhere to anywhere, but may be
simpler to install a private copy of R to do the building.

3.3 The packages I installed do not appear in the HTML help system.
===================================================================

HTML help only works for packages installed in `rwXxxx\library'.

To update the HTML help files after you have installed a binary package,
run at the R prompt.

     > link.html.help()

(Using `install.packages()' does this for you.  The source-code
installation also does this automatically, and if you have that
installed you can use (preferably)

     cd rwXxxx\src\gnuwin32\help
     make indices

instead.)

3.4 My functions are not found by the HTML help search system.
==============================================================

The following conditions need to hold for functions in a package you
installed.

   * the package is installed in `rwXxxx\library'.

   * the package contains a `CONTENTS' file in top-level directory (a
     few of the binary distributions do not).

   * you updated the indices as described in the answer to Q3.3 after
     installing the package.

If those all hold true, this works for us.


4 Windows Features
******************

4.1 What should I expect to behave differently from the Unix version of R?
==========================================================================

   * R commands can be interrupted by <Esc> in `rgui.exe' and
     <Ctrl-break> or <Ctrl-C> in `rterm.exe': <Ctrl-C> is used for
     copying in the GUI version.

   * Command-line editing is always available, but is much simpler than
     the readline-based editing on Unix. For `rgui.exe', the menu item
     `Help | Console' will give details.

   * The commands history is saved between sessions only on `rgui.exe',
     and it is always saved.

   * Using `help.start()' does not automatically send help requests to
     the browser: use `options(htmlhelp=T)' to turn this on.

   * The HTML help system can only access packages installed in the
     standard place.

   * Paths to files (e.g. in `source()') can be specified with either
     "/" or "\\".

   * `system()' is slightly different: see its help page and that of
     `shell()'.

4.2 I hear about some nifty features: please tell me about them!
================================================================

You have read the `README'? There are file menus on the R console,
pager and graphics windows. You can source and save from those menus,
and copy the graphics to `png', `jpeg', `bmp', `postscript' or
`metafile'. There are right-click menus giving shortcuts to menu items,
and optionally toolbars with buttons giving shortcuts to frequent
operations.

If you resize the R console the `options(width=)' is automatically set
to the console width (unless disabled in the configuration file).

The graphics has a history mechanism. As the README says:

     `The History menu allows the recording of plots. When plots have
     been recorded they can be reviewed by <PgUp> and <PgDn>, saved and
     replaced.  Recording can be turned on automatically (the Recording
     item on the list) or individual plots can be added (Add or the
     <INS> key). The whole plot history can be saved to or retrieved
     from an R variable in the global environment.

     There is only one graphics history shared by all the windows
     devices.'

The R console and graphics windows have configuration files stored in
the `RHOME\etc' directory called `Rconsole' and `Rdevga'; you can keep
personal copies in your `HOME' directory. They contain comments which
should suffice for you to edit them to your preferences. For more
details see `?Rconsole'.  From `rw1010' there is a Preferences editor
invoked from the `Edit' menu which can be used to edit the file
`Rconsole'.


5 Workspaces
************

5.1 My workspace gets saved in a strange place: how do I stop this?
===================================================================

Have you changed the working directory?: see Q5.2.

5.2 How do I store my workspace in a different place?
=====================================================

Use the `File | Change Dir' menu item to select a new working
directory: this defaults to the last directory you loaded a file from.
The workspace is saved in the working directory. You can also save a
snapshot of the workspace from the `Save Image' menu item.

5.3 Can I load workspaces saved under Unix/GNU-Linux?
=====================================================

Yes. The converse (saving on Windows, loading on Unix) also works.


6 The R Console and Fonts
*************************

6.1 I would like to be able to use Japanese fonts
=================================================

for example, in the console and to annotate graphs.

We believe this is possible by setting suitable fonts in the Rconsole
and Rdevga configuration files (see Q4.2). You can specify additional
fonts in Rdevga, and use them by

     par(font=, font.lab=, font.main=, font.sub=)

Nineteen fonts are specified (as 1 to 19) by default: you can add to
these (up to 13 more) or replace them.

6.2 I don't see characters with accents at the R console, for example in ?text.
===============================================================================

You need to specify a font in Rconsole (see Q4.2) that supports latin1
encoding. The default, Courier New, does on our systems, as does
FixedSys.  This may be a problem in other locales, especially for
non-Western European languages.

6.3 When using Rgui the output to the console seems to be delayed.
==================================================================

This is deliberate: the console output is buffered and re-written in
chunks to be less distracting. You can turn buffering off or on from
the Misc menu or the right-click menu: <Ctrl-W> toggles the setting.

If you are sourcing R code or writing from a function, there is another
option. A call to the R function `flush.console()' will write out the
buffer and so update the console.

6.4 Long lines in the console or pager are truncated.
=====================================================

They only *seem* to be truncated: that $ at the end indicates you can
scroll the window to see the rest of the message. Use the horizontal
scrollbar or the <CTRL+arrow> keys to scroll horizontally, or the
horizontal scrollbar.


7 Building from Source
**********************

7.1 How can I compile R from source?
====================================

Get the R sources. Suppose you want to compile R-1.1.0.

     tar zxvf R-1.1.0.tgz
     cd R-1.1.0
     cd src\gnuwin32

Now read the `INSTALL' file and set up all the tools needed. Then you
can just use `make', sit back and wait. (A complete build takes about
15 minutes on a 300MHz PII with a fast local disc.)

You may need to compile under a case-honouring file system: we found
that a `samba'-mounted file system (which maps all file names to lower
case) did not work.

7.2 How do I debug code that I have compiled and dyn.load-ed?
=============================================================

First, build a version of the R system with debugging information by

     make clean
     make DEBUG=T

and make a debug version of your package by

     make DEBUG=T pkg-mypkg

Then you can debug by

     gdb /path/to/rwXxxx/bin/Rgui.exe

However, note

   * gdb will only be able to find the source code if we run in the
     location where the source was compiled (`rwXxxx/src/gnuwin32' for
     the main system, `rwXxxx/src/library/mypkg/src' for a package),
     unless told otherwise by the `directory' command. It is most
     convenient to set a list of code locations via `directory'
     commands in the file `.gdbinit' in the directory from which `gdb'
     is run.

   * It is only possible to set breakpoints in a DLL after the DLL has
     been loaded. So a way to examine the function `tukeyline' in
     package `eda' might be

               gdb ../../../../bin/Rgui.exe
               (gdb) break WinMain
               (gdb) run
               [ stops with R.dll loaded ]
               (gdb) break R_ReadConsole
               (gdb) continue
               [ stops with console running ]
               (gdb) continue
               Rconsole> library(eda)
               (gdb) break tukeyline
               (gdb) clear R_ReadConsole
               (gdb) continue

     Fortran symbols need an underline appended.

   * Windows has little support for signals, so the usual idea of
     running a program under a debugger and sending it a signal to
     interrupt it and drop control back to the debugger does not work
     with `mingw32' version of `gdb'.  It does often work with the
     `cygwin' version.

   * We have seen examples in debugging problems with Windows events
     that the `cygwin gdb' was able to catch but which terminated the
     `mingw32 gdb'.

If you have an X server available on the PC, there is a version of `DDD'
available that runs under the cygwin emulation layer (follow the links
at `http://sourceware.cygnus.com/cygwin') and provides a graphical user
interface to `gdb'.  Another (Windows-native) GUI for `gdb' is
`Insight', from
`ftp://ftp.xraylith.wisc.edu/pub/khan/gnu-win32/cygwin/ports/'.

7.3 How do I include C++ code?
==============================

You need to do two things:

(a) Write a wrapper to export the symbols you want to call from R as
`extern "C"'.

(b) Include the C++ libraries in the link to make the DLL. Suppose
`X.cc' contains your C++ code, and `X_R.cc' is the wrapper. Then build
the DLL by (`gcc-2.95.x')

     g++ -c X.cc X_R.cc
     dlltool --export-all-symbols --output-def X.def X_R.o
     dllwrap -o X.dll --def X.def X.o X_R.o -lstdc++

or (VC++)

     cl /MT /c X.cpp X_R.cpp
     link /dll /out:XX.dll /export:X_main X.obj X_R.obj

and call the entry point(s) in `X_R', such as `X_main'.  Construction
of static variables will occur when the DLL is loaded, and destruction
when the DLL is unloaded, usually when R terminates.

7.4 The output from my C code disappears. Why?
==============================================

The `Rgui.exe' console is a Windows application: writing to `stdout' or
`stderr' will not produce output in the console. (This will work with
`Rterm.exe'.)  Use `Rprintf' or `REprintf' instead. These are declared
in header file `R_ext/PrtUtil.h'.

7.5 The output from my Fortran code disappears. Why?
====================================================

Writing to Fortran output writes to a file, not the `Rgui' console.
Use one of the subroutines `dblepr', `intpr' or `realpr' documented in
the _`Writing R Extensions'_ manual.



Last edited 2000 April 28 by Brian Ripley <ripley@stats.ox.ac.uk>