@comment -*-texinfo-*-
@comment $Id: NEWS.texi,v 1.37 2005-03-10 16:57:14 Singular Exp $
@comment this file contains the News about Singular versions
@comment Unix
@ifclear VERSION
@include version.texi
@end ifclear

@majorheading NEWS in SINGULAR @value{VERSION}

@ifclear singularmanual
@macro nref{what}
\what\
@end macro
@end ifclear

@ifset singularmanual
@macro nref{what}
@ref{\what\}
@end macro
@end ifset

The current version @value{VERSION} is an update to the new
release series version 2-0. 

Singular version 2 is generally much faster than any previous
version of Singular, due to a rewrite of major parts of the Singular
kernel (e.g., the kernel has a new memory manager and a new polynomial
arithmetic) and due to new and better implemented algorithms (e.g., for
computing resolutions and determinants).

Besides theses internal changes, Singular version 2 offers many new
features and functionlities (which were partly already incorporated in
the 1-3 series). E.g., a native Windows distribution, an Emacs user
interface, a new help system, 16  new libraries, etc.

All these changes are explained in more detail below.

@heading Efficiency Improvements
The following table shows some timings which compare the efficincy of
Singular version 1-2-3 and Singular version 2. All times are in seconds
and were obtained on an AMD Athlon with 700 MHz, 128 MB RAM, running
Linux.

@multitable @columnfractions .15 .15 .25 .15 .15 .15
@item @strong{Example} @tab @strong{Comp} @tab @strong{Ring} @tab @strong{1-2} @tab @strong{2-0} @tab @strong{Speedup}
@item @uref{http://www.singular.uni-kl.de/Benchmarks/Singular/mora_1.sing,,mora_1} @tab std  @tab 32003,x(1..3),ds @tab 82 @tab 9.4 @tab 8.7
@item @uref{http://www.singular.uni-kl.de/Benchmarks/Singular/mora_9.sing,,mora_9} @tab std  @tab 32003,x(1..14),ds @tab 9600 @tab 96 @tab 100
@item @uref{http://www.singular.uni-kl.de/Benchmarks/Singular/homog_gonnet.sing,,homog_gonnet} @tab std  @tab 32003,x(1..18),dp @tab 33 @tab 8.9 @tab 4.5
@item @uref{http://www.singular.uni-kl.de/Benchmarks/Singular/homog_cyclic_8.sing,,homog_cyclic_8} @tab std  @tab 32003,x(1..9),dp @tab 1873 @tab 472 @tab 4.0
@item  @uref{http://www.singular.uni-kl.de/Benchmarks/Singular/cyclic_8.sing,,cyclic_8} @tab std @tab 32003,x(1..8),dp @tab >47800 @tab 478 @tab >100
@end multitable

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

@heading General Changes
@table @asis
@item @strong{Windows distribution}
created with Installshield, includes Cygwin, Singular, and (optionally)
XEmacs, distributed as several self-extracting archives. Contains @sc{Singular} help
in a Windows Help format (the file @code{Manual.hlp}).
@item @nref{Emacs user interface}
the recommended interface for using @sc{Singular}
@item @code{ESingular}
new program for an out-of-the-box, pre-customized Emacs which runs
Singular
@item @nref{The online help system}
choose in which browser the on-line help is displayed;
@*wildcard expansion of help topics
@*new layout of html manual pages
@item @nref{Source code debugger}
interactive debugging of procedures written in the @sc{Singular}
language
@item @nref{example}
Provide on-line examples for all kernel and library commands.
@item file/directory layout of distribution
@code{Singular/<version>/}
@item http://www.singular.uni-kl.de
New WWW home-site of @sc{Singular}
@item RPM versions of Singular
including integration into KDE
@end table

@heading Extensions of the ring concept

@table @asis
@item new coefficient domains: arbitrary long real and complex numbers
@item no restriction on number of ring variables
@item no restriction on number of parameters
@c @item TBC: DegBound on exponent values
@c @item TBC: parameters over real/complex
@c @item TBC: declaration with "ring of ring".
@end table

@heading New @sc{Singular} libraries

Reorganisation of libraries into "Categories".
@table @asis
@item @nref{intprog_lib} procedures for computing toric ideals
@item @nref{toric_lib} procedures for Integer Programming using Groebner bases
@item @nref{spectrum_lib} procedures for computing spectra
@item @nref{mregular_lib}  procedures for computing the Castelnuovo-Mumford regularity
@c @item @nref{mprimdec}
@c procedures for primary decomposition of modules
@item @nref{mondromy_lib}
procedures for computing the monodromy of a singularity
@item @nref{gmspoly_lib}, @nref{gmssing_lib}
procedures for the Gauss-Manin connection of a singularity
@item @nref{spcurve_lib}
procedures for CM codimension 2 singularities
@item @nref{triang_lib}
procedures for decomposing zero-dimensional ideals
@item @nref{solve_lib}
procedures for solving polynomial systems
@item @nref{surf_lib}
visualization of curves and surfaces with @code{surf}
@item @nref{reesclos_lib}
Rees Algebra and integral closure of an ideal
@item @nref{brnoeth_lib}
Brill-Noether algorithm, Weierstrass semigroups and AG codes
@item @nref{stratify_lib}
Algorithmic stratification by the Greuel-Pfister algorithm
@item @nref{paramet_lib}
parametrization of curves
@item @nref{rinvar_lib}
Invariant rings of reductive groups
@item @nref{zeroset_lib}
Procedures for roots and factorization
@item @nref{qhmoduli_lib}
Moduli spaces of sqh-singularities
@end table

@heading Changes in @sc{Singular} libraries
Many procedures were moved into different libraries,
the documentation of libraries was generally improved and
some libraries renamed:
@table @asis
@item @nref{ainvar_lib}
renamed @code{invar.lib} to @code{ainvar.lib}
(see also @code{rinvar.lib}, @code{finvar.lib}).
@item @nref{deform_lib}
renamed procedures @code{T1, T2, T12} to @code{T_1, T_2, T_12}.
@item @nref{poly_lib}
new procedures numerator/denominator
@item @nref{linalg_lib}
included @code{jordan.lib} in @code{linalg.lib}
@end table

@heading New @sc{Singular} functions

@table @asis
@item @code{convhull, simplex}
TODO: docu, tests
@item @nref{division}
Extension of lift: @code{division(M,SM)} returns a list @code{[T,U,R]}
with @code{SM*U+R=M*T}
@item @nref{breakpoint}
sets a debugger breakpoint
@item @code{div}
integer division omitting remainder
@item @nref{ERROR}
interrupts computation in current procedure and returns with error
message to top-level
@item @nref{fglmquot}
calculate ideal quotions using FGLM-techniques
@item @nref{leadmonom}
returns the leading monomial of a polynomial or a vector as a polynomial
or vector whose coefficient is one
@item @nref{highcorner}
returns the smallest monomial not contained in and ideal/module
@item @nref{hres}
calculate free resolution of homogenous ideal using Hilbert-driven
algorithm.
@item @nref{minor}
with an optional third argument minors modulo a standard basis will be computed
@item @nref{mpresmat}
calculate module representing the multipolynomial resultant matrix
@item @nref{uressolve}
compute all complex roots of a zerodimensional ideal
@item @nref{vandermonde}
solve Vandermonde linear system
@item @nref{jet}
extended for series expansions of rational expressions
@item @nref{reduce}
extended for reduced normal form of rational expressions
@end table

@heading @sc{Singular} functions whose syntax/semantics has changed
@table @asis
@item @nref{division}
arguments swapped w.r.t. version 2-0-1 and before
@item @nref{coeffs}
Extended possible syntax to
@code{coeffs(ideal,ideal)} and @code{coeffs(module,module)} which is
equivalent to @code{coeffs(ideal,ideal,p)} and
@code{coeffs(module,module,p)} where @code{p} is a polynomial (i.e.,
monomial) consisting of all ring variables.
@item @nref{execute}
parenthesis around argument of execute is now @strong{mandatory}.
@item @nref{lift}
new implementation (unified handling of isSB and not isSB case); new
optional third argument (a matrix name), which, if given, stores the
"matrix of units"
@item @nref{bareiss}
new implementation after Lie-Saunders, much faster
@item @nref{example}
run example for all kernel commands.
@c @item @nref{fetch}
@item @nref{print}
Finer-grained control for formatted output.
@item @nref{pause}
can be called with argument, must be called with parenthesis.
@item @nref{option}
new options: @code{oldStd}, @code{redThrough}, @code{notBuckets}
@end table

@heading Changes of command-line options and system resources
@table @asis
@item @code{--browser}, @code{--allow-net}, @code{--emacs}, @code{--sdb}
new command-line options
@ifset singularmanual
(@pxref{Command line options})
@end ifset
.
@item @nref{system}
values of command-line options can be inspected/set at run-time with
@code{system(<option>[,<new_value])}.
@item @code{.singularrc}
system administrators can put a "global" @code{.singularrc} file into
the directories where @sc{Singular} libraries reside
@ifset singularmanual
(@pxref{Startup sequence})
@end ifset
.
@item @code{libreadline}
if found, a shared version of the @code{readline} library is linked-in
dynamically at run-time. If not found, @code{readline} is emulated.
@end table

@heading Internal Changes
@table @asis
@item new data structures for monomials and polynomials
Makes polynomial arithmetic significantly faster: Especially for block -
or weighted orderings.
Bucket representation of polynomials in std;
Ring change during std, res and bareiss computations
(resulting in more speed and less space consumption).
@item new memory management
Results is less memory usage, faster memory allocation/free, less
fragmentation, much better locality of reference.
@item factorization
revisited, missing cases implemented
@end table

@heading Porting

@itemize @bullet
@item
@code{libreadline} works only with ix86-libc5,
ix86-libc6,HPUX_9,HPUX_10
@item Singular is available for ix86-libc5, ix86-libc6, HPUX_9, HPUX_10,
SunOS-4, SunOS-5, IRIX-6, ix86-Win (runs on Windows 95/98/NT4/2000),
FreeBSD 4.2, MacOS X
@end itemize