New libraries:

• enumpoints.lib: enumerating rational points ( enumpoints_lib)
• sagbigrob.lib: Sagbi-Groebner basis of an ideal of a subalgebra ( sagbigrob_lib)
• puiseuxexpansion.lib: Puiseux expansions over algebraic extensions ( puiseuxexpansions_lib)
• integralbasis_lib: Integral basis in algebraic function fields: new version ( integralbasis_lib)

Changes in the kernel/build system:

• ABI change: all number routines (n_...) have only coeffs as last argument, functions with ring as last argument are removed
• PATH is not changed for system("sh",..) (use SingularBin)
• hilb avoids int overflow (also in degree, stdhilb)
• liftstd (with 2 arguments) improved ( liftstd)
• noether improved ( noether), use in groebner(I,"HC") for faster results for local orderings, 0-dimensional ideals ( groebner).
• letterplace routines improved ( LETTERPLACE)
• info file is now singular.info instead of singular.hlp
• update for using FLINT 2.8.x

New commands:

• Letterplace: dim, rightStd for qrings ( LETTERPLACE)
• Letterplace: map, fetch, imap ( map, fetch, imap)

New libraries:

• decomp.lib: functional decomposition of polynomials ( decomp_lib)
• hodge.lib: algorithms for Hodge ideals ( hodge_lib)
• tateProdCplxNegGrad.lib: sheaf cohomology on product of projective spaces ( tateProdCplxNegGrad_lib)

Changes in the kernel/build system:

• liftstd (with 2 arguments) improved ( liftstd)
• building on Cygwin with shared libaries
• building the manual via --enable-doc-build

• renamed poly.lib to polylib.lib ( polylib_lib)

New libraries:

• interval.lib: interval arithmetic ( interval_lib)
• maxlike.lib: algebraic statistics ( maxlike_lib)
• nchilbert.lib: Hilbert series for LetterPlace algebras ( nchilbert_lib)
• polyclass.lib: class of polynomials ( polyclass_lib)
• recover.lib: Hybrid numerical/symbolical algorithms ( recover_lib)
• redcgs.lib: Reduced Comprehensive Groebner Systems ( redcgs_lib)
• ringgb.lib: coefficient rings ( ringgb_lib)
• sets.lib: Sets ( sets_lib)
• stanleyreisner.lib: T1 and T2 for a general Stanley-Reiser ring ( stanleyreisner_lib
• systhreads.lib: multi-threaded objects ( systhreads_lib)

Changed libraries:

• classify_aeq.lib: new procedure classSpaceCurve ( classify_aeq_lib)
• grobcov.lib: new version ( grobcov_lib)
• modular.lib: parallel version for verification via system("verifyGB",I)

New commands:

• system("verifyGB",I): test, if I is a Groebner basis (using parallel processes)
• Letterplace: modulo,syz,lift,liftstd, rightStd ( LETTERPLACE)

Changes in the kernel/build system:

• update for using FLINT 2.6.x and for FLINT 2.7.0
• Singular can be build with NTL or FLINT or both (if non is availabel, factroize and gcd will not work.)

Changes in the kernel/build system:

• Letterplace: modulo,syz,lift,liftstd ( LETTERPLACE)

News for version 4-1-3

New libraries:

• invar.lib: Invariant theory invar_lib
• moddiq.lib: ideal quotient and saturation moddiq_lib
• ncModslimgb.lib: modular Groebner bases for G-algebras ncModslimgb_lib

Changed libraries:

• chern.lib: new version ( chern_lib)
• grobcov.lib: new version ( grobcov_lib), new functions ConsLevels, Levels, Grob1Levels, DifConsLCSets

Changes in the kernel/build system:

• improved gcd and multiplication via FLINT
• improved lift (and related)
• port to polymake 3.5.x
• rational functions via flint ( flintQ)
• free algebra over Z ( LETTERPLACE)
• adaptions/functions for Singular.jl(https://github.com/oscar-system/Singular.jl)

New libraries:

• arnoldclassify.lib: Arnol'd Classifier of Singularities ( arnoldclassify_lib)
• difform.lib: Procedures for differential forms ( difform_lib)
• dmodideal.lib: Algorithms for Bernstein-Sato ideals of morphisms ( dmodideal_lib)
• fpalgebras.lib: Generation of various algebras in the letterplace case ( fpalgebras_lib)
• ncrat.lib: non-commutatie rational functions ( ncrat_lib)

Changed libraries:

• freegb.lib: lpDivision, lpPrint ( freegb_lib)
• fpadim.lib ( fpadim_lib)
• schreyer.lib: deprecated
• goettsche.lib: new, extended version (The Nakajima-Yoshioka formula up to n-th degree,Poincare Polynomial of the punctual Quot-scheme of rank r on n planar points Betti numbers of the punctual Quot-scheme of rank r on n planar points)( goettsche_lib)
• grobcov.lib: small bug fix ( grobcov_lib)

Changes in the kernel/build system:

• integrated xalloc into omalloc: (./configure --disable-omalloc)
• improved heuristic for det ( det)
• improved reading of long polynomials
• improved groebner bases over Z coefficients
• code for free algebras (letterplace rings) rewritten (using now the standrad +,-,*,^,std,...) ( LETTERPLACE)
• new commands rightstd ( rightstd (letterplace))
• extended twostd to LETTERPLACE ( twostd (letterplace), twostd (plural))
• pseudo type polyBucket
• new type smatrix: sparse matrix (experimental) ( smatrix).
• extended coef to ideals ( coef).
• error and signal handling in libSingular ( libSingular).
• updated gfanlib to version 0.6.2
• port to NTL 11 (needs C++11: gcc6 or -std=c++11), which does not conflict with polymake (needs C++14)

New syntax:

• alias: may be used as a prefix to a variable declaration. Can only be used in procedure headings. ( General command syntax).

New command:

• fres: improved version of sres: computes a (not necessarily minimal) free resolution of the input ideal/module, using Schreyer's algorithm. ( fres, sres).

Extended commands:

• pseudo ordering L allows setting of limits for exponents in polynomials ( Pseudo ordering L, attrib for maxExp)
• %,mod: also for poly operands ( poly operations).
• delete: extended to intvec, ideal, module ( delete).
• syz ( syz), lift ( lift), liftstd ( liftstd), intersect( intersect): with a specified GB algorithm

New libraries:

• classify2.lib: Classification of isolated singularities of corank <=2 and modality <= wrt. right equivalence over the complex numbers according to Arnold's list. ( classify2_lib)
• goettsche.lib: Goettsche's formula for the Betti numbers of the Hilbert scheme of points on a surface, Macdonald's formula for the symmetric product ( goettsche_lib)
• combinat.lib, modules.lib, methods,lib, nets.lib: a more mathematical view of modules ( combinat_lib: combinatorics), ( methods_lib: construct procedures), ( modules_lib: free resolutions), ( nets_lib: pretty printing)
• ncHilb.lib: Hilbert series of non-commutative monomial algebras ( ncHilb_lib)
• realclassify.lib: Classification of real singularities( realclassify_lib)
• rootisolation.lib: real root isolation using interval arithmetic( rootisolation_lib)
• rstandard.lib: Janet bases and border bases for ideals ( rstandard_lib)

Changed libraries:

• chern.lib: new version ( chern_lib)
• gitfan.lib: new (incompatible) version ( gitfan_lib)
• grobcov.lib: new version ( grobcov_lib)

Changes in the kernel/build system:

• port to polymake 3.x.x
• port to NTL 10 with threads (needs also C++11: gcc6 or -std=c++11)
• p_Invers is only a helper for p_Series: now static
• p_Divide is now p_MDivide, pDivive is a new routine

Syntax changes:

• new (additional) form of ring definitions: (for example ring R=QQ[x,y,z];) ( General syntax of a ring declaration)
• new (additional) form of multi-indicies: (for example i(1,2,3,4,5)) ( Names)
• changed behaviour of charstr ( charstr)
• new data type cring to describe the coeffient rings, to be used for the new definitions for (polynomial) rings ( General syntax of a ring declaration)
• new command ring_list to access the parts used to contruct polynomial rings ( ring_list, ringlist)
• extended polynomial ring construction: also from lists produced by ring_list
• new attribute ring_cf for ring ( attrib)
• printing of rings changed to match cring names ( charstr)

New libraries:

• new library: classifyMapGerms.lib: standard basis of the tangent space at the orbit of an algebraic group action ( classifyMapGerms_lib)
• new library: ffmodstd.lib: Groebner bases of ideals in polynomial rings over algebraic function fields( ffmodstd_lib)
• new library: nfmodsyz.lib: syzygy modules of submodules of free modules over algebraic number fields( nfmodsyz_lib)
• new library: curveInv.lib: invariants of curves ( curveInv_lib)
• new library: gfan.lib: interface to gfanlib ( gfan_lib)
• extended library: interface to polymake merged into polymake_lib
• new library: tropicalNewton.lib: Newton polygon methods in tropical geometry ( tropicalNewton_lib)
• new library: schubert.lib: some procedures for intersction theory ( schubert_lib)

Changed libraries:

• classify_aeq.lib: new procedures ( classify_aeq_lib)
• grobcov.lib: new version ( grobcov_lib)
• ncfactor.lib: factorization in some noncommuative algebras ( ncfactor_lib) with new routine ncfactor ( ncfactor)
• primdec.lib: new option "subsystem" ( primdec_lib)

Changes in the kernel:

• improved mapping of polynomials/ideals/...
• port to gcc 6
• port to gfanlib 0.6 (requires C++11, i.e. gcc >=4.3)
• port to NTL 10
• port to polymake 3.0
• port to readline 7
• sba works for global orderings, also for coefficient types Z and Z/m
• std works for all orderings, also for coefficient types Z and Z/m with local/mixed orderings
• factorize works for polynomial rings over ZZ

Experimental stuff:

• module customstd_lib: modify std ( satstd)

New commands:

• align ( align)
• branchTo ( procs with different argument types)
• -> ( proc expression)

Change in ring handling:

• typeof( qring ) returns "ring"

New libraries:

• algemodstd.lib: Groebner bases of ideals in polynomial rings over algebraic number fields( algemodstd_lib)
• arr.lib: arrangements of hyperplanes ( arr_lib)
• brillnoether.lib: Riemann-Roch spaces of divisors on curve ( brillnoether_lib)
• hess.lib: Riemann-Roch space of divisors on function fields and curves ( hess_lib)
• gradedModules.lib: graded modules/matrices/resolutions ( gradedModules_lib)

Changed libraries:

• revised polymake interface ( polymake_lib, polymake_so)
• revised gfanlib interface ( gfanlib_so)
• Presolve::findvars ( findvars, variables)
• Ring::addvarsTo ( addvarsTo)
• Ring::addNvarsTo ( addNvarsTo)
• Ring::hasAlgExtensionCoefficient ( hasAlgExtensionCoefficient)
• Schreyer::s_res ( s_res)
• grobcov.lib (grobcovK) ( grobcov_lib) with new routines AddCons ( AddCons), AddConsP ( AddConsP).
• normaliz.lib (for normaliz >=2.8) ( normaliz_lib)
• renamed groebnerFan to groebnerFanP in polymake.lib ( polymake_lib)
• renamed fVector to fVectorP in polymake.lib ( polymake_lib, polymake_so)

Version 4-0-1 is a bug fix release. New feature: attribute ring_cf for ring.

Availability

SINGULAR is available as source code and for Linux, Mac OS X, Windows, FreeBSD and SunOS-5.

Version 4-0-0 is a milestone relase of Singular. The new release series 4 aims for an entirely modularized architecture simplifying connectivity with other systems and paving the way for parallel computations. As a first step in modularization, the new release features an internal structural separation of coefficient rings and polynomial rings. This allows for a flexible integration of new coefficient rings.

SINGULAR 4-0-0's list of new functionality and significant improvements further extends that of the 3-1-6/7 prerelease series.

New functionality

• de Rham cohomology of complements of algebraic varieties ( derham_lib)
• Gromov-Witten numbers of elliptic curves ( ellipticcovers_lib)
• classification of isolated complete intersection singularities in characteristic 0 ( classifyci_lib)
• parametrization of orbits of unipotent actions ( orbitparam_lib)
• F5-like Groebner basis algorithm ( sba)
• element-wise application of functions to data structures ( apply)
• support for debugging libraries ( ASSUME)

Improved functionality

• Groebner cover for parametric ideals ( grobcov_lib)
• normalization of affine rings ( normal_lib)
• classification of real singularities ( realclassify_lib)
• GIT-fans ( gitfan_lib)
• algebraic/transcendental field extensions
• Non-commutative subsystem
• an abstraction layer for parallel computations ( parallel_lib)
• run-time loading of supplementary kernel code ( Dynamic modules)
• interpreter language support for name spaces ( package)

Availability

SINGULAR is available as source code and for Linux, Mac OS X, Windows, FreeBSD and SunOS-5.