GSL - GNU Scientific Library
============================

Installation Instructions
=========================

GSL follows the standard GNU installation procedure.  To compile GSL
you will need an ANSI C-compiler.  After unpacking the distribution
the Makefiles can be prepared using the configure command,

  ./configure

You can then build the library by typing,

  make

Both static and shared versions of the libraries will be compiled by
default.  Compilation of shared libraries can be turned off by
specifying the `--disable-shared' option to `configure', e.g.
  
  ./configure --disable-shared

If you encounter problems building the library try using the above
option, because some platforms do not support shared libraries.  If
you change any compilation options you will need to remove any
existing compiled files with,

  make clean

before running "make" again, so the new settings take effect.

For notes about problems with specific platforms and compilers see the
next section of this file (below).

An extensive test suite is available.  After compiling the library
with "make", it can be invoked with "make check" at the top level.
The test output should be directed to a file rather than a terminal,
with the command,

   make check > log 2>&1

to allow any errors to be examined in detail.  By default, only test
failures are shown.  To see the complete output, set the environment
variable GSL_TEST_VERBOSE=1.  Use "make -k check" to continue running
the remaining tests in the event of failures.

If you run the tests and get some failures, please see the notes on
platform specific problems below.  If you find failures that are not
mentioned, please report them to bug-gsl@gnu.org.

The library can be installed using the command,

  make install

The default installation directory prefix is /usr/local.  Installing
in this directory will require root privileges on most systems (use
"su" or "sudo").

The installation directory can be changed with the --prefix option to
configure.  Consult the "Further Information" section below for
instructions on installing the library in another location or changing
other default compilation options.

When building from source, GNU packages are compiled with debugging
symbols enabled by default (CFLAGS="-g -O2").  It's part of the
philosophy that anyone should be able to examine any program on the
system.

                    ------------------------------

Platform Specific Compilation Notes
===================================

This section documents any known issues with installing GSL on
specific platforms.

  * General hints for all platforms
  * AIX
  * Compaq/DEC Alpha
  * HP-UX
  * IRIX
  * MacOS X / PowerPC
  * Microsoft Windows
  * OpenBSD
  * OS/2
  * Solaris

Hints for any platform
======================

1) If there are problems building the library try using

        ./configure --disable-shared --disable-dependency-tracking

This will turn off the compilation of shared libraries and dependency
tracking and may allow the build process to complete successfully.

If you get any problems try this first.

2) If your compiler uses the C99-style inline keyword, use

    ./configure CFLAGS="-DGSL_C99_INLINE -g -O2"

to avoid problems with duplicate function definitions.  For gcc this
is handled automatically.  See the file gsl_inline.h for the
preprocessor definitions that are used.

3) If you want to pass C++ functions with exceptions to GSL, the
library needs to be compiled with the GCC option -fexceptions

    ./confugire CFLAGS="-fexceptions ..."

to allow C++ exceptions to be handled.

4) With gcc-4.3.2 the tests in the poly/ directory fail due to a
compiler optimization bug which is fixed in later versions of GCC
(http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38478).

FAIL: y.real, gsl_complex_poly_complex_eval ({-2.31 + 0.44i, 4.21 - 3.19i, 0.93 + 1.04i, -0.42 + 0.68i}, 0.49 + 0.95i) (-1.68450788000000018 observed vs 1.82462012000000007 expected) [9]
FAIL: y.imag, gsl_complex_poly_complex_eval ({-2.31 + 0.44i, 4.21 - 3.19i, 0.93 + 1.04i, -0.42 + 0.68i}, 0.49 + 0.95i) (-0.30943988 observed vs 2.30389411999999982 expected) [10]

With gcc-2.95/2.96 the tests fail in the eigen/ directory.  This is
due to a compiler optimization bug which causes errors in the
manipulation of complex numbers.  

If you encounter these problems, install a different version of gcc.

5) Attempts to run 'strip' on the static library libgsl.a will probably
produce a broken library (it is known to happen with GNU binutils
strip, and probably affects others too). The libgsl.a ar archive made
by libtool contains files with the same filenames from different
directories, and this causes the strip program to overwrite these
archive entries.  If you need to produce a compact version of the
library compile without -g instead of using strip.

make install-strip does not work, due to a minor problem with autoconf
which is fixed in the 2.5 development version of autoconf.  In the
meantime compile without -g instead if you need to reduce the file size.

6) The configure script can fail with a segmentation fault on bash-2.01

    $ ./configure
    Segmentation fault

This is due to a bug in bash, related to the MAIL environment
variable.  To work around it use 

    $ unset ENV MAIL MAILPATH
    $ ./configure

which should avoid the problem.

Hints for AIX
=============

For compilation problems with the native compiler xlc, try disabling
shared libraries,

    setenv CC 'xlc'
    setenv CFLAGS '-O -qmaxmem=8192'
    ./configure --disable-shared
    make

If you compile with higher optimisation -O3 you will also need
-qstrict.  The -O3 flag causes the -nostrict option to be
enabled. This affects the accuracy of the results and causes some of
the tests to fail.

If you get errors like

 ld: 0711-593 SEVERE ERROR: Symbol C_BSTAT (entry 635) in object siman_tsp.o:
          The symbol refers to a csect with symbol number 0, which was not
          found. The new symbol cannot be associated with a csect and
          is being ignored.

this is due to problems with some versions of the IBM assembler.  Try
compiling with CFLAGS="-g0" as a workaround.  For details and other
solutions see https://www-304.ibm.com/support/docview.wss?uid=isg1IZ98134 and
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46072

If you get the error,

   ld: 0711-781 ERROR: TOC overflow. 

you can try building the library with a larger linker
table-of-contents by setting LDFLAGS before compilation,

   ./configure LDFLAGS="-Wl,-bbigtoc" 

On older versions of AIX (e.g. 4.2) the size of the command-line is
limited to 24kb, which causes linking to fail (due to the large number
of files to be linked). Unfortunately this limit cannot be increased.
To link the library you may need to use a manual approach of
incrementally combining the object files in smaller groups. 

On more recent versions of AIX (e.g >= 5.1) use

  chdev -l sys0 -a ncargs=NNN

to increase the allowed number of arguments. NNN is the amount of
space measured in 4k blocks (default 6, maximum 1024)

Hints for Compaq/DEC Alpha
==========================

When comping with GCC use the -mieee and -mfp-rounding-mode options 
as appropriate, e.g.

    ./configure CFLAGS="-mieee -mfp-rounding-mode=d -g -O2"

The library should compile successfully with Compaq's C compiler on
Tru64 Unix 'cc' using the -std, -ieee and -fprm options.  Use

    ./configure CC=cc 
    make CFLAGS="-std -ieee -fprm d"

to build the library this way.

Use GNU tar to unpack the tar file, as Tru64 tar gives an error
halfway through.

Hints for HP-UX
===============

The default mode of the HP-UX C compiler does not use ANSI C.

To compile GSL you need to select ANSI C mode with the following
configuration option:

      ./configure CFLAGS="-Ae"  

To switch on optimization use CFLAGS="-Ae -O".

Hints for IRIX (SGI)
====================

The library should be compiled with the CFLAGS option
-OPT:IEEE_NaN_inf=ON to ensure correct IEEE arithmetic.  The tests in
sys/ will fail without this option.  The older deprecated option
-OPT:IEEE_comparisons=ON will also work.

The 32 bit IRIX compiler gives warnings about "long double" not being
supported. These can be ignored or turned off with,

   ./configure CFLAGS="-woff 728" 

or 

   make CFLAGS="-woff 728"

The compiler also gives warnings about certain libraries that are "not
used for resolving any symbol". This is harmless and the warnings can
be ignored.

You may get warnings about " /usr/bin/ld: arg list too long" when
building shared libraries.  If so, try increasing the ncargs kernel
parameter with the systune(1m) command.

For 64-bit compilation use the following options,

  ./configure CC=cc CFLAGS="-64" LDFLAGS="-64" 

or for gcc

  CFLAGS="-mabi-64" LDFLAGS="-mabi=64 -mips4 -L/usr/local/lib/mabi=64"

Hints for MacOS X and PowerPC
=============================

To install in /usr/local on MacOS systems, do "sudo make install" to
gain root privileges.

Note that GSL contains files with filenames of 32 characters or more.
Therefore you need to be careful in unpacking the tar file, as some
MacOS applications such as Stuffit Expander will truncate filenames to
31 characters.  Using GNU tar and gunzip directly is the safe way to
unpack the distribution.

There are problems with dynamic linker, so the library should be
compiled with,

  ./configure --disable-shared --disable-dependency-tracking

It has been reported that shared libraries can be built if MacOS X
specific versions of libtool, automake and autoconf from
http://fink.sourceforge.net/ are installed, and the GSL source is
reconfigured from scratch (./autogen.sh; ./configure; make)

To avoid warnings about long-double, use the flag

  CFLAGS="-Wno-long-double ....(other options here)"

in addition to the normal compilation options.

If you get make check failures with OS X 10.x try using CC=gcc-4.2 or
CC=clang since the llvm compiler has bugs that make the tests fail.

The GCC 3.3 compiler shipped by Apple contains a bug which causes the
wavelet tests to fail on "data untouched" tests at optimisation level
-O2.  You may be able work around this by compiling with CFLAGS="-O1
..." instead.

F J Frankin <MEP95JFF@sheffield.ac.uk> reported that some early
versions of GCC-2.95 have a problem with long argument lists on PPC
architecture, and this prevents GSL from compiling correctly (e.g. the
test program in the blas directory gives a segmentation fault when
run).  This problem is fixed in more recent versions of GCC.


Hints for Microsoft Windows
===========================

GSL should compile with GCC under Cygwin on Microsoft Windows.  
There is a gsl package in the standard Cygwin distribution which
contains any patches needed.

With Mingw/MSYS some floating point issues have been reported which
cause failures in the monte/ test directory.

Hints for OpenBSD
=================

As of July 2001 the OpenBSD log1p() function on i386 causes failures
in the gsl complex tests.  The configure script has been hardcoded to
substitute gsl_log1p instead on OpenBSD.  The log1p() bug has been
reported and so may be fixed in future versions of OpenBSD.

Hints for OS/2
==============

The configure script fails to detect the function 'isnan', leading to
a slew of errors 'isnan redefined'.

To work around this problem, run configure and edit the resulting
config.h file to comment out the line which defines HAVE_ISINF.

Hints for Solaris
=================

If you are using the Sun compilers then the library should be compiled
with the Sun C compiler 'cc', not 'CC' which is the C++ compiler.

The Sun compiler tools are stored in non-standard directories -- make
sure that all the compiler and linker tools (cc, ar, ranlib, ld) are
on the PATH.  A typical PATH should include the directories
/opt/SUNWspro/bin:/usr/ccs/bin:/usr/ucb in that order.

For example,

  $ PATH=/opt/SUNWspro/bin:/usr/ccs/bin:/usr/ucb:$PATH
  $ ./configure CC=cc CFLAGS=-O

If you see configure output 
  
   checking for ar... :

it means that 'ar' has not been found, and the library will fail to
build.

If you use the Sun compiler you should use the Sun linker and
assembler.  If you use GCC, you can use the GNU linker and assembler
or the Sun linker and assembler.

There may be some warnings about "end of loop code not reached". These
can be ignored -- they come from the do { ... ; return ; } while(0)
statement in the GSL_ERROR macro.

If you get errors such as symbol `gsl_complex_rect' is	multiply-defined
you will need to use ./configure CFLAGS="-DGSL_C99_INLINE -g -O2"

                    ------------------------------

Further information on the standard GNU installation procedure
==============================================================

The sections below describe the general features of the standard GNU
installation procedure.

Basic Installation
==================

   These are generic installation instructions.

   The `configure' shell script attempts to guess correct values for
various system-dependent variables used during compilation.  It uses
those values to create a `Makefile' in each directory of the package.
It may also create one or more `.h' files containing system-dependent
definitions.  Finally, it creates a shell script `config.status' that
you can run in the future to recreate the current configuration, a file
`config.cache' that saves the results of its tests to speed up
reconfiguring, and a file `config.log' containing compiler output
(useful mainly for debugging `configure').

   If you need to do unusual things to compile the package, please try
to figure out how `configure' could check whether to do them, and mail
diffs or instructions to the address given in the `README' so they can
be considered for the next release.  If at some point `config.cache'
contains results you don't want to keep, you may remove or edit it.

   The file `configure.in' is used to create `configure' by a program
called `autoconf'.  You only need `configure.in' if you want to change
it or regenerate `configure' using a newer version of `autoconf'.

The simplest way to compile this package is:

  1. `cd' to the directory containing the package's source code and type
     `./configure' to configure the package for your system.  If you're
     using `csh' on an old version of System V, you might need to type
     `sh ./configure' instead to prevent `csh' from trying to execute
     `configure' itself.

     Running `configure' takes a while.  While running, it prints some
     messages telling which features it is checking for.

  2. Type `make' to compile the package.

  3. Optionally, type `make check' to run any self-tests that come with
     the package.

  4. Type `make install' to install the programs and any data files and
     documentation.

  5. You can remove the program binaries and object files from the
     source code directory by typing `make clean'.  To also remove the
     files that `configure' created (so you can compile the package for
     a different kind of computer), type `make distclean'.  There is
     also a `make maintainer-clean' target, but that is intended mainly
     for the package's developers.  If you use it, you may have to get
     all sorts of other programs in order to regenerate files that came
     with the distribution.

Compilers and Options
=====================

   Some systems require unusual options for compilation or linking that
the `configure' script does not know about.  You can give `configure'
initial values for variables by setting them in the environment.  Using
a Bourne-compatible shell, you can do that on the command line like
this:
     CC=c89 CFLAGS=-O2 LIBS=-lposix ./configure

Or on systems that have the `env' program, you can do it like this:
     env CPPFLAGS=-I/usr/local/include LDFLAGS=-s ./configure

Compiling For Multiple Architectures
====================================

   You can compile the package for more than one kind of computer at the
same time, by placing the object files for each architecture in their
own directory.  To do this, you must use a version of `make' that
supports the `VPATH' variable, such as GNU `make'.  `cd' to the
directory where you want the object files and executables to go and run
the `configure' script.  `configure' automatically checks for the
source code in the directory that `configure' is in and in `..'.

   If you have to use a `make' that does not supports the `VPATH'
variable, you have to compile the package for one architecture at a time
in the source code directory.  After you have installed the package for
one architecture, use `make distclean' before reconfiguring for another
architecture.

Installation Names
==================

   By default, `make install' will install the package's files in
`/usr/local/bin', `/usr/local/man', etc.  You can specify an
installation prefix other than `/usr/local' by giving `configure' the
option `--prefix=PATH'.

   You can specify separate installation prefixes for
architecture-specific files and architecture-independent files.  If you
give `configure' the option `--exec-prefix=PATH', the package will use
PATH as the prefix for installing programs and libraries.
Documentation and other data files will still use the regular prefix.

   If the package supports it, you can cause programs to be installed
with an extra prefix or suffix on their names by giving `configure' the
option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.

Optional Features
=================

   Some packages pay attention to `--enable-FEATURE' options to
`configure', where FEATURE indicates an optional part of the package.
They may also pay attention to `--with-PACKAGE' options, where PACKAGE
is something like `gnu-as' or `x' (for the X Window System).  The
`README' should mention any `--enable-' and `--with-' options that the
package recognizes.

   For packages that use the X Window System, `configure' can usually
find the X include and library files automatically, but if it doesn't,
you can use the `configure' options `--x-includes=DIR' and
`--x-libraries=DIR' to specify their locations.

Specifying the System Type
==========================

   There may be some features `configure' can not figure out
automatically, but needs to determine by the type of host the package
will run on.  Usually `configure' can figure that out, but if it prints
a message saying it can not guess the host type, give it the
`--host=TYPE' option.  TYPE can either be a short name for the system
type, such as `sun4', or a canonical name with three fields:
     CPU-COMPANY-SYSTEM

See the file `config.sub' for the possible values of each field.  If
`config.sub' isn't included in this package, then this package doesn't
need to know the host type.

   If you are building compiler tools for cross-compiling, you can also
use the `--target=TYPE' option to select the type of system they will
produce code for and the `--build=TYPE' option to select the type of
system on which you are compiling the package.

Sharing Defaults
================

   If you want to set default values for `configure' scripts to share,
you can create a site shell script called `config.site' that gives
default values for variables like `CC', `cache_file', and `prefix'.
`configure' looks for `PREFIX/share/config.site' if it exists, then
`PREFIX/etc/config.site' if it exists.  Or, you can set the
`CONFIG_SITE' environment variable to the location of the site script.
A warning: not all `configure' scripts look for a site script.

Operation Controls
==================

   `configure' recognizes the following options to control how it
operates.

`--cache-file=FILE'
     Use and save the results of the tests in FILE instead of
     `./config.cache'.  Set FILE to `/dev/null' to disable caching, for
     debugging `configure'.

`--help'
     Print a summary of the options to `configure', and exit.

`--quiet'
`--silent'
`-q'
     Do not print messages saying which checks are being made.

`--srcdir=DIR'
     Look for the package's source code in directory DIR.  Usually
     `configure' can determine that directory automatically.

`--version'
     Print the version of Autoconf used to generate the `configure'
     script, and exit.

`configure' also accepts some other, not widely useful, options.

