

  --- This `README' file corresponds to Singular-Factory version 4.1 ---


		  README file for Singular-Factory
		  ================================

NOTE: The copyright of Singular-Factory is described in the
      file COPYING

Overview
========
1.  What is Factory?
2.  Comments, Questions, Bug Reports
3.  Installation
4.  Distribution
5.  Prerequisites
6.  Stream IO
7.  Diagnostic Messages
8.  GF(q) Tables
9.  A Note on Singular
10. Factory Template Instantiation
11. Documentation
12. Examples and Tests
13. Remark on Characteristic Sets
14. Adding new code
15. Nomenclature
16. Limitations

1. What is Factory?
===================
  Factory is a C++ class library that implements a recursive representation
of multivariate polynomial data.  It was developed by Ruediger Stobbe
and Jens Schmidt at the University of Kaiserslautern as an independent and
self-contained part of the computer algebra system Singular (developed by
G.-M. Greuel, G. Pfister and H. Schoenemann) and is now developed by Martin Lee.

  Factory handles sparse multivariate polynomials over different
coefficient domains, such as Z, Q and GF(q), as well as algebraic
extensions over Q and GF(q) in an efficient way.  Factory includes
algorithms for computing univariate and multivariate gcds, resultants,
chinese remainders, and algorithms to factorize multivariate polynomials
and to compute the absolute factorization of multivariate polynomials with integer
coefficients.

  The interface to the polynomial system of Factory is provided by a single
class `CanonicalForm' which can deal with elements of the coefficient
domain as well as polynomials.  Using operator overloading, you can handle
polynomial data similarly to built-in types such as the machine integers.
For example, to add two polynomials one simply uses the `+' operator.
Because of this, Factory is easy to use even if you are not familiar with
C++ programming.

  There are a couple of utility classes provided by Factory such as lists,
arrays, polynomial maps, etc.  These make the usage more comfortable.

2. Comments, Questions, Bug Reports
====================================
  Factory is a project in evolution.  That means there is no guarantee that
Factory is bug free.  I am sure that there are bugs or at least features.
If you find bugs or if you find a strange behavior of the library, please
let me know (e-mail: singular@mathematik.uni-kl.de>).
Comments and questions are welcome, too.

  Factory version 1.2c and newer define an string
`FACTORYVERSION' describing the version of the library.  The external
variable `factoryConfiguration' (not present in versions 1.2c and 1.3a)
describes the options Factory has been configured with.  Please include the
version number and the configuration options in your bug reports.  You may
either use the UNIX utility `what' to get this information (`what libcf.a')
or compile and run something similar to this:

  #include "factory.h"
  main() { cout << FACTORYVERSION << "; " << factoryConfiguration << endl; }

3. Installation
===============
NOTE: If you have received this Factory distribution together with Singular
you do not have to worry about compilation or installation at all.  The
installation procedure for Singular should do everything for you.  For more
information, see the section "A Note on Singular".

  For further information on factory's configure options see also ./configure --help.

  The installation procedure on UNIX platforms conforms more or less to the GNU
standard:

  ./configure --without-Singular; make; make check; make install;

  In general, this `README' as well as the `INSTALL' file are written for
UNIX platforms.  However, you may find less specific information on the
configuration and installation process which is useful for other platforms,
too.

4. Distribution
===============
  The latest stable version of Factory is always available from

		www.singular.uni-kl.de

  For the latest development version visit

               www.github.com/Singular

5. Prerequisites
================
  You need GNU make to build and install Factory.  Furthermore, I strongly
recommend to build Factory with GNU CC.  To build
Factory and to link your programs with Factory you need the GNU Multiple
Precision Library (GMP).

Configure options:
------------------
  --with-gmp=<path to GMP> enabled by default

  For full functionality NTL (www.shoup.net/ntl) is required.

Configure options:
------------------
  --with-ntl=<path to NTL> enabled by default

  For optimal preformance we recommend to use FLINT (www.flintlib.org) and to use
  Singular's memory manager omalloc

Configure options:
------------------
  --with-flint=<path to FLINT> enabled by default
  --with-omalloc               disabled by default
  --with-omalloc-dir=<path to omalloc>

6. Stream IO
============
  For use with other systems which have their own IO routines to print
polynomials it is possible to switch off Factory's stream IO.

Configure options:
------------------
  --disable-streamio      build Factory without stream IO


7. Diagnostic Messages
======================
Factory has three types of diagnostic messages:
o Assertions (implemented by the "ASSERT macros" in `cf_assert.h') are used to
  ensure preconditions before running some algorithm.  A typical example is
  to test f != 0 before dividing by f.
o Debug output (implemented by the "DEBOUT macros" in `debug.h'/`debug.cc')
  is used to trace complex algorithms, e.g. factorization.
o Timing information may be accumulated and printed using the "TIMING macros"
  in `timing.h'.

  Since all diagnostic messages are implemented using preprocessor macros,
they will completely cease when disabled, thus avoiding any impact on
speed.  By default, all diagnostic messages are disabled.

Configure options:
------------------
  --enable-assertions     build Factory with assertions activated
  --enable-timing         build Factory so it will print timing information
  --enable-debugoutput    build Factory so it will print debugging information

8. GF(q) Tables
===============

  Factory uses addition tables to calculate in GF(p^n) in an efficient way.

  They can be created with `make gengftables'.  Building the tables takes quite
   a while!

9. A Note on Singular
=====================
  If you have received this Factory distribution together with Singular you
do not have to worry about compilation or installation at all.  The
installation procedure for Singular should do everything for you.

10. Factory Template Instantiation
==================================
  There are a couple of classes provided by Factory such as lists, arrays,
etc, which may be used to derive new abstract data types from already
existing ones.  Factory uses them itself, e.g. to return the result of a
factorization (a list of factors), and you may use them to create new
derived abstract data types.  These classes are realized using C++
templates, which are instantiated in one single file namely ftmpl_inst.cc .

11. Documentation
=================
  So far there are only preliminary versions of a user/reference manual and
a tutorial ("A quick start into Factory").  Please do not expect them to
be error-free or even complete.  For this reason, the documentation is not
included in the source code archive (`factory-<version>.tgz').  Instead, the
sources and compiled DVI files reside in `factory-doc-prelim.tgz'. They will
unpack into a directory `factory-doc-prelim/'.


12. Examples and Tests
======================
  The directory `examples/' in the Factory source directory contains some
example applications for Factory.

  'make check' will run some simple test as well.

13. Remark on Characteristic Sets
=================================
Algorithms for manipulation of polynomial ideals via the characteristic set
methods (e.g., calculating the characteristic set and the irreducible
characteristic series) are now incorporated into factory.
If you want to learn about characteristic sets, the next is a good point
to start with:
    Dongming Wang:
    An Implementation of the Characteristic Set Method in Maple.
    In: Automated Practical Reasoning: Algebraic Approaches
    (J. Pfalzgraf and D. Wang, eds.), Springer-Verlag,
    Wien-New York, 1995, pp. 187-201.

14. Adding new code
===================
  If you like to add new code 'foo.cc/foo.h' add 'foo.cc' to 'Makefile.am' under
'SOURCES' and 'foo.h' under 'factory_headers'. If your new functions should be
available via factory's global interface 'factory.h' add

/*MAKEHEADER PUBLIC ONLY*/
foo.h

to 'factory.template' and enclose the functions in 'foo.h', that you like to
add, by '/*BEGINPUBLIC*/' and '/*ENDPUBLIC*/'.

15. Nomenclature
================
  Factorization related functions are contained in files with the prefix 'fac'.
Functions operating on CanonicalForm's are contained in files with the prefix
'cf'. Functions operating on the internal structures of a CanonicalForm are
contained in files with the prefix 'int'. Exceptions are gfops.cc/.h,
ffops.cc/.h, imm.cc/.h as they use intrinsic data types.

16. Limitations
===============
  The largest characteristic of a finite field is limited to 536870909. The
number of elements of a finite fields represented by Conway polynomials has to
be < 2^16 (see gfops.cc).

