     [file version.texi not included]

NEWS in SINGULAR VERSION
************************

The current version VERSION is an update to the release series version 2-0.

Changes with respect to version 2-0-3:

Factorizing algorithms revisited
================================

Starting with version 2-0-4, we use NTL (by Victor Shoup) for factoring univariate polynomials. The multivariate factoring code in libfac/factory does now also work over algebraic extension fields.

Help system is configurable via LIB/help.cnf
============================================

The help browsers of Singular can be configured via the file LIB/help.cnf, also the addition of new help browsers is possible.

Extensions of the ring concept
==============================

new coefficient domains: arbitrary long real and complex numbers

no restriction on number of parameters

degree bound on exponent values (maximum is now 2^31, standard 2^15)

non-positives weights get a better handling (converts wp/Wp to ws/Ws)

handle blocks of mixed orders correctly

maximal prime characteristic is now 2147483629 instead of 32003

Changes in SINGULAR libraries
=============================

The documentation of libraries was generally improved.

equising_lib
     procedures esStratum, isEquising now also for reducible polynomials

     new procedures: tau_es (codim of mu-const stratum in semi-universal def. base); esIdeal ((Wahl's) equisingularity ideal)

gaussman_lib
     added bernstein: roots of the Bernstein polynomial of t

hnoether_lib
     HNdevelop, reddevelop, essdevelop are obsolete, replaced by hnexpansion

     multsequence is "repaired" (since branches computed by hnexpansion et al) are now ordered according to the needs of multsequence.

     newtonpoly needs no longer that ordering of the basering is ls

     new procedures: is_NND      test if f is Newton non-degenerate

homolog_lib
     new procedures: depth, fitting, flatteningStrat, isCM, isFlat, isLocallyFree, isReg, KoszulHomology, tensorMod, Tor

matrix_lib
     in proc tensor(A,B):  check if ncols(A)==0

normal_lib
     new procedure: deltaLoc(f,S);      (sum of) delta invariant(s) at conjugated singular points

     proc genus makes now use of is_NND of hnoether.lib

primdec_lib
     optimizations again

solve_lib
     procedure laguerre_solve ignores no longer the 2nd parameter (precision of internal computation)

      new procedure simplexOut:     prints solution of simplex in nice format

Internal Changes
================

normal form computation uses
     Bucket representation of polynomials.

factorization
     revisited, missing cases implemented

NTL
     NTL is used for univariate factorization

source code
     adapted for use with gcc 3.1/3.2, gmp 4.x

Porting
=======

  * Singular is available for ix86-libc5, ix86-libc6, HPUX_9, HPUX_10, SunOS-4, SunOS-5, IRIX-6, ix86-Win (Windows 95/98/ME/NT/2K/XP), FreeBSD 4.x, MacOS X Windows 95/98/ME/NT/2K/XP and MacOS X

  * MP functionality is not available on Windows 95/98/ME/NT/2K/XP and MacOS X.

  * Singular 2-0-2 was the last version for MacOS 9