the behavior of return in the debugger has changed: it now stops in the debugger at the next available opportunity
filenames starting with ~/ will have the tilde replaced by the home directory
the D language, in which the Macaulay 2 interpreter is written, is now type-safe
during compilation of Macaulay 2, as much of the computation as possible is now done to satisfy the make-target all, with the resulting files placed in a staging area, ready for quickly satisfying the make-target install.
during compilation of Macaulay 2, it is now possible to keep the architecture independent files in a separate directory tree, saving time if versions for multiple architectures are to be built. Including those files in a source tar file will allow the distribution of a fat source tar file, speeding up compilation.
pressing the RET key in the Macaulay 2 interaction buffer on a line containing a source file name and line number will open up the source file at that position in a new buffer. This allows error messages to be treated with dispatch.
the behavior of setup has changed, in that the commands that set the paths are now placed in separate files in the home directory of the user, and those files are sourced only if they are present. That enables the user to continue to share the usual init files on multiple machines, even though Macaulay 2 may be installed in various different locations.
hilbertFunction is now faster at computing power series expansions
A new division algorithm has been implemented in rings with inverses, where the monomials can involve negative exponents, and hence are not well-ordered. See division in polynomial rings with inverses.
a bug in irreducibleCharacteristicSeries, upon with minimalPrimes depends, was fixed. Now the new ring supporting the characteristic series will have variables with the same names and degrees, but the ordering of the variables and the monomial ordering will be different. This ensures that homogeneity will be preserved. Also, for convenience, the routine now returns a sequence, instead of a list, suitable for immediate parallel assignment.
minors has been altered so the ideal of n by n minors that it provides for negative values of n is the unit ideal.
parts has been altered so that for multigraded rings, it does not use the first component of the degree vector. New functionality has been added.
heft vectors are now automatically computed, heft vectors
the description of a ring provided by describe is now abbreviated by making use of run length encoding
browsers started by viewHelp are now run in a separate process group so they don't die when Macaulay 2 terminates
get has been fixed so it returns an error message if the process associated with the pipe has died
searchPath now does what the documentation said it would do
comparison of rings with == instead of === is no longer supported
the output operation s<<x, when s is a string, has been changed so that if a file with filename s is already open, that file will be used instead of opening a new file with the same name, erasing the data already written to the file
tensor product of a module with a ring has been modified so it will make a ring map between the two rings that is derived from the names of the variables
GF now uses Conway polynomials when possible. Maps between Galois fields made with them are now easy to produce with map(E,F)
the degrees in symmetric algebras have been corrected
the default for polynomial rings over polynomial rings is now to join the degree vectors of monomials in the base to the degree vectors of the top level monoid, usually resulting in a multigraded ring. For example, QQ[x][y] is now bigraded.
inverting a noninvertible matrix results in an error message now
export, given a string (rather than a symbol) will now make a new symbol with that name, even if a symbol with the same name already exists in another visible package
homomorphisms of modules over different rings with respect to a ring homomorphism between them, are now supported. Composition, coimage (replacing pushForward1), and kernel work. An option has been added to basis to ask it to return such a homomorphism.
basis will now check finite dimensionality in advance, to avoid running out of memory
Functions and types associated with hypertext and documentation have been isolated in a new package called Text (missing documentation ), which gets loaded automatically by beginDocumentation.
the file layout system, as described by Layout, formerly called LAYOUT, now supports separation of architecture independent files from architecture dependent files