reduce-algebra/README

                       REDUCE - Open Source release


                      July 2013, then February 2014

Tiny updates to this file just to try to keep the credits to other
projects that are used up to date. As of Feb 2014 the revision number
at Sourceforge is 2337, and this seems to correspond to an average
activity rate of a bit over 3 checkins per day.

                             December 2010

This project just reached revision 1000 in the Sourceforge subversion
repository. This feels like something of a landmark.


                              March 2009


This is the REDUCE algebra system, which was originally developed by
Tony Hearn. A bibliography somewhere in this tree reports some of the
large numbers of papers that have been written about or relying on
REDUCE.


                                     Arthur Norman.  March 2009


The BULK of the files in this tree are subject to the (modified) BSD license,
as shown below. There are some components that are subject to more restrictive
terms (notably the FOX GUI Toolkit, used in one version of the code here, is
under LGPL).

===========================================================================

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the relevant copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNERS OR CONTRIBUTORS
BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.


===========================================================================

The CSL version of Reduce has started to migrate to use the wxWidgets
library rather than FOX (see below). wxWidgets is under its own license
which is LGPL 2 (or later) plus some permissive exceptions for the
distribution of applications linked against the library. A full
archive is wxWidgets source is included and that contains full details.



Note that the directory csl/fox contains a modified version of the
FOX toolkit (www.fox-toolkit.com) version 1.6 which is subject to
LGPL 2.1. Note explicitly that while an unmodified version of FOX can be
linked into an application and the resulting version may be distributed
without hindrance even the smallest change that has not been accepted by
the FOX central site can only be used under the terms of the LGPL.

Within the FOX directory the "utils" subdirectory contains a program
reswrap.cpp that is used while building FOX. I do not see any cause for
anybody to even want to distribute a binary of that, but to satisfy the
GPL better I have put a copy of the GPL in the directory with it. No part of
reswrap itself ends up in the main programs built here, and its status is
thus rather like that of gcc and other tools.

The FOX test programs were originally held within the FOX directory, but
they are subject to the GPL not the LGPL or any more benign license. I have
moved them to a separate directory to make it unambiguous that there are at
most here as mere aggregation, and the standard build sequences here make
even the presence of that directory optional. I do not intend to provide or
distribute binary copies of any of them ever, and so there should not be any
complications at all on that front.


The "gnuplot" package is used with REDUCE and its license indicates that
it may be redistributed freely, but that modified versions may only be
circulated in the form of patch files against the official release. The
version included here is an original un-modified copy. Well actually right now
there is no version included with Reduce. This is because Sourceforge policy
is that if we include any binary then we must also put the corresponding
source into the Sourceforge Release system. Putting a copy of a snapshot
of the gnuplot source there seems both clumsy and asks for confusion as and
when gnuplot gets updated, so this area is under review!

The CSL source directory contains material derived from Adobe font metrics,
and these metrics it works can be found on many sites - they can be
downloaded directly from Adobe's ftp site but also they are included
with many existing software packages in forms that clearly state that
they are available for redistribution and that the authors of those
packages have checked license conditions carefully. The set of files
I use here came with "teTeX 2" where these terms are carefully set
out and where the package is very well established and widely used so
there would have been plenty of opportunity for concerns about rights
to be aired. I have not altered the metric files at all.

There is a copy of the "distorm" x86 disassembler, which originated from
Gil Dabah and licensed under the modified BSD license. See
http://ragestorm.net/distorm.

I use adjusted versions of Computer Modern Fonts derived from the Blue Sky
Research and Y&Y inc versions but which are now freely available for general
use. Their copyright is held by the American Mathematical Society, and the
versions here should yield exactly the same font metrics as the original
versions.

The Truetype-format fonts are from the BaKoMa Computer Modern Font collection
as distributed via "ctan", and the associated permissive license is included
in the directory where they are held. This set of files and its associated
.tfm metrics are gradually replacing my use of other font data.

An implementation of the MD5 message digest is due to Eric Young and
comes from an implementation of SSL, and is subject to what is in essence the
modified BSD license. The original and full version of the license terms
is included where that code is incorporated.

Various other parts within CSL were contributed by NAG Ltd and by various
students and others, including J O'Connell, M O Seymour, but were made
available to me and to Codemist for inclusion within CSL.

The files in the "psl" directory come from ZIB and are some of the ones
that they used with the Reduce Development System. As shown there these are
also under a BSD license - see the HP_disclaimer.txt that confirms a release
from one of the earlier major copyright holders.

crlibm is a "correctly rounded maths library" subject to LGPL 2.1. It was
fetched from http://lipforge.ens-lyon.fr/www/crlibm/ but needed (minor)
aljustment to let it build here.

The Latin Modern Fonts and Latin Moder Math Fonts are from
http://www.gust.org.pl/projects/e-foundry and copies of the original
archives containing them are in csl/support-packages along with unpacked
a copy of the GUST-FONT-LICENSE.txt file and relevant README files.
There are two uses of derived works, and the GUST License (which is
an instance of the Latex Project Public License) requires that an
explanation of what is covered and what changes are made is placed in
a prominent place (eg here!).
In csl/cslbase/wxfonts there are re-packed font files. Merely placing the
files in a tree that is distinct from the .zip file that formed the
original distribution makes this a derived (and changed) work. But I
have also needed to (use fontforge to) convert each .oft file so I also
have a .ttf version since my Windows code appeared not to render glyphs
from the .otf versions. This should not alter character shapes or metrics
but may degrade rendering. I have also extracted from these fonts a
series of bitmaps that record which characters are present in the fonts.
This is done because I was not instantly able to do this at the point of
rendering, and because it then helps me use font substitution for any
missing characters. In use these fonts will be set up as application-
specific private fonts rather than as globally and permenantly installed
ones, so the chances of causing confusion for other software ought to
be low. The font directories that are to be distributed as part of
a binary release of the software contain READE files etc alongside the
actual fonts, and executable software will respond to a "--help" option
by displaying a message that contains a brief citation of the fonts and
how to recover original official versions.
I believe that since I have not changed font shapes, metrics or coverage
and since the distribution is not set up to make the fonts available
generally - just to have them used as application-private resources - that
renamking the fonts (to avoid confusion) is not necessary here.
But it is important to record that the fonts and derived information are
NOT subject to the full permissions of the BSD License and that any
use that envisages moving them away from the code here or altering the
messages about them that "--help" displays needs to be done only after
careful review of the actual licenses.




                                           A C Norman (acn1@cam.ac.uk)