## E.1 News and changes

# NEWS in SINGULAR 4-0-2

## News for version 4-0-2

- renamed algemodstd_lib to nfmodstd_lib
- renamed derham_lib to deRham_lib
- new library: brillnoether.lib
- new library: chern.lib
- new library: hess.lib
- new library: graal_lib
- new library: GND.lib
- grobcov.lib (grobcovK) ( grobcov_lib) with new routine ConsLevels ( ConsLevels), removed AddCons AddConsP.

## News for version 4-0-2

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(renamed to nfmodstd_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 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)

## News for version 4-0-1

Version 4-0-1 is a bug fix release.

New feature: attribute `ring_cf` for `ring`.

## News for version 4-0-0

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.

User manual for Singular version 4-0-2, 2015, generated by texi2html.