Change log for Magma V2.11-9 (Released 26/10/2004)

Commutative Algebra

·GrÃ¶bner basis computation with the HFE option has been sped up by about 10% to 20%.

·Bugs in multivariate resultants and discriminants with trivial inputs have been fixed.

Differential Operator Rings

·For some differential operators the Newton polygon was incorrect. This has been fixed. A related error in the calculation of a Newton polynomial has been repaired.

Geometry

·An error in projective closure maps involving projective spaces with more than one grading has been fixed.

Groups

·A bug in the setting of universes of matrix group orbits has been rectified. Bug reported by Eric Rains.

·A bug in making maximal subgroups of PSp(4,p) : 2, where p = 1 mod 12, has been fixed. Bug reported by Colva Roney-Dougal.

·Crashes in !! have been fixed.

Invariant Theory

·A bug in the computation of primary invariants over quadratic fields has been fixed. Bug reported by Eric Rains.

Rings and Fields

·A bad value for the Discriminant parameter to MaximalOrder of algebraic fields will now result in a runtime error rather than a crash.

·The handling of elements in function fields defined by non monic polynomials has been fixed.

·AllIrreduciblePolynomials now works properly on all 64-bit systems.

·subset now correctly takes a FldPr rather than a FldPrElt.

·Expansion of function field elements at a place has been fixed.

·Finding the UnderlyingField of a function field has been fixed.

·Maximal printing for non-simple number fields now shows all generators.

·SubOrders and EquationOrders of orders defined over non-monic polynomials were wrongly returned as orders.

Sets and Sequences

·IsNull now works correctly for GSets.

·Sequences can now be used as indices for indexed sets.

System

·In Windows, redirecting output from the Magma process to a file now results in line-by-line buffering, which is more convenient for long-running jobs.

·SetMemoryLimit and GetMemoryLimit now work properly on 64-bit systems.