Magma V2.15-14 Patch Notes

Algebraic Geometry¶

• A memory leak in Saturate has been removed.

Coding Theory¶

• A crash in SternsAttack has been fixed. Reported by R. Niebuhr.

Commutative Algebra¶

• Crashes in the function CohomologyDimension (related to Regularity) and Twist have been fixed. Reported by E. Rains.

Cyclotomic Fields¶

• A memory problem occuring in the case of a sparse cyclotomic field of small degree where the conductor is a large integer, has been fixed.

Graphs¶

• A problem in graphs when nauty data was not present has been fixed. Reported by D. Leemans.

Groups¶

• A crash in FPGroup when applied to a regular permutation group has been fixed. Bug reported by S. Humphries.
• A problem defining homomorphisms with domain an abelian group having some trivial generators has been fixed. Previously this generated a runtime error.
• A problem with the group name used by the print option of pQuotient has been fixed. The problem was caused by a recent bug fix. Reported by G. Havas.
• A crash in the matrix groups base and strong generating set code has been fixed. Bug reported by M. Giudici.

Groups of Lie type¶

• RelativeRootElement was incorrectly trying to coerce its output into the twisted group.
• Order was giving incorrect values when the group was constructed from a root subdatum with smaller root space than the original root datum.
• Kernel works for homomorphism from a group of Lie type which is known to be injective.
• IsSimple has been implemented for groups of Lie type. The intrinsic IsIrreducible is now deprecated for this type.

Number Fields¶

• A string of problems with non-simple extensions defined over a number field having a non-integral denominator have been fixed. Without this fix an internal error would be triggered.

Polynomial Rings¶

• A problem with non-unique elements in polynomial quotient rings has been fixed. Reported by M. Stoll.
• A crash in powering of elements in a chain of recursive rings has been fixed. Reported by M. Stoll.

Representation Theory¶

• A bug in SymmetricRepresentation (which computes an irreducible module for a symmetric group), which occurs when the non-Specht algorithm is used, has been fixed; the matrices being returned were acting on the left rather than the right as Magma expects. Reported by M. Wildon.