Seminormalization, a package by Karl Schwede and Bernard Serbinowski for computing seminormalization of rings, has been published.
SumsOfSquares, a package by Diego Cifuentes, Thomas Kahle, Pablo A. Parrilo, and Helfried Peyrl for sums of squares, has been published.
The function installPackage now returns, as its value, the package that was installed. This makes it more convenient to both install and check a package, because one can type check installPackage "FOO".
The roots command is now handled by the MPSolve library, and is more robust, but no longer takes an optional argument Unique.
The Complexes package has new data types and routines for homological algebra. Eventually, it will replace the current facilities for homological algebra. We are making this available in order to get feedback from users before making this change. Please email the authors with any and all comments or suggestions.
The PARI library has been removed. Its functionality has been subsumed by the MPSolve library (for the roots function for finding roots of a univariate polynomial), and the FLINT library, for integer factorization and primality testing.
The Boost.Stacktrace library has been added for printing stack traces in case of a crash.
Primality testing, provided by isPrime, is now handled by the FLINT library.
Factorization of integers, provided by factor(ZZ), is now handled by the FLINT library.
The FLINT library, and several others, no longer need to be patched while building Macaulay2. This involved a reorganization of the way memory management is done in the engine and the interpreter. As a result, we can use versions of several basic libraries as provided by the operating system, including GNU MP,MPIR,MPFR, and the NTL library.
The CompleteIntersectionResolutions package now has an implementation of the dual of the (infinite) Tate resolution of any module over a complete intersection $R$ as a finitely generated module over $R[t_1..t_c]$, the ring of Eisenbud operators. As a byproduct, this gives another method for computing the global $Ext_R(M,N)$. Also implemented layered resolutions (in the sense of Eisenbud-Peeva) of Cohen-Macaulay modules over $R$.
The ReesAlgebra has new functionality, with the defaults changed to make the computation faster.