E.1 News and changes
====================


NEWS in SINGULAR 2-0-4
**********************



The current version 2-0-4 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

<font size="-1">
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; User manual for <a href="http://www.singular.uni-kl.de/"><i>Singular</i></a> version 2-0-4, October 2002,
generated by <a href="http://www.gnu.org/software/texinfo/"><i>texi2html</i></a>.
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