SpectralSequences, a package by Adam Boocher, Nathan Grieve, Eloisa Grifo, Gregory G. Smith, and Thanh Vu for spectral sequences, has been added.
SectionRing, a package by Andrew Bydlon for computing the section ring of a Weil Divisor., has been added.
K3Carpets, a package by David Eisenbud, Frank-Olaf Schreyer for K3 double structure on scrolls, has been added.
ChainComplexOperations, a package by David Eisenbud for sym2, wedge2, chi2 of a ChainComplex, has been added.
NumericalCertification, a package by Kisun Lee for testing NumericalAlgebraicGeometry, has been added.
PhylogeneticTrees, a package by Nathaniel Bushek, Ruth Davidson, Elizabeth Gross, Pamela Harris, Robert Krone, Colby Long, AJ Stewart, Robert Walker, and Robert Walker for invariants for group-based phylogenetic models, has been added.
MonodromySolver, a package by Cvetelina Hill, Anders Nedergaard Jensen, Kisun Lee, Anton Leykin, and Jeff Sommars for solving polynomial systems via monodromy, has been added.
ReactionNetworks, a package by Timothy Duff, Kisun Lee, and Anton Leykin for reaction networks, has been added.
PackageCitations, a package by Aaron Dall for citation of Macaulay2 packages, has been added.
NumericSolutions, a package by Corrado Possieri, and Antonio Tornambe for solving systems of polynomial equalities, has been added.
GradedLieAlgebras, a package by Clas Löfwall and Samuel Lundqvist for computations in graded Lie algebras, has been added.
InverseSystems, a package by David Eisenbud for equivariant Macaulay inverse systems, has been added.
Pullback, a package by Drew Ellingson and Karl Schwede for pullback of rings, has been added.
EngineTests, a package by Michael E. Stillman and Jakob Kroeker for a test suite for the Macaulay2 engine, has been added.
SVDComplexes, a package by Frank Schreyer and Mike Stillman for SVD of a complex, including nonminimal resolutions over the reals, has been added.
RandomComplexes, a package by Frank Schreyer and Mike Stillman for random complexes over fields or the integers, has been added.
improved packages:
Polyhedra has been rewritten by Lars Kastner for improved performance. Many bugs have been fixed, and there are now a large number of tests. Some changes are not backward compatible. Some changes include:
Fan, is no longer a collection of Cone objects, but contains a matrix of rays (over ZZ), and a list of lists of integer indices, indicating the maximal cones. Well-defined-ness is no longer automatically checked. Use isWellDefined(Fan)
Polyhedron, is now a wrapper for the homogenized cone.
Cone, has basically the same functionality, except that not everything is computed ahead of time.
faces, now returns a list of lists of integer indices. There are two new functions for recovering the old behavior: facesAsCones (for fans and cones), and facesAsPolyhedra for polyhedra and polyhedral complexes.
An important difference is that objects of these classes can no longer be used as keys into hash tables, since these objects are implemented as mutable hash tables. In particular === no longer works on cones. Instead, use a sorted list of e.g. vertices and lineality space.
If you need the old behavior, load the package OldPolyhedra. However, if possible, change your code to run with the new package.
functionality added or improved:
The functions toDual and fromDual have been improved and moved to the new package InverseSystems: they are now compatible with linear changes of coordinates.