Magma V2.28-12 Patch Notes

Character Theory¶

• A new signature for intrinsic BaseRing has been added - BaseRing of a character table or other sequence of characters returns the minimal cyclotomic field such that all character values in the given sequence can be coerced into the field.

Commutative Algebra¶

• A small problem in Variety for ideals with non-standard monomial orders has been fixed. Reported by M. Grassl.
• A serious hang and related crash occurring for a certain type of very large Groebner basis computation over the rational field has been fixed. Reported by D. Platt.

Complex Field¶

• The computation of roots of polynomials over the complex field which involved computing even powers has been improved (so negligible real parts are not included when possible).

Curves¶

• The functions LPolynomial and ZetaFunction have been fixed for certain problem cases in very small characteristic. Reported by E. Costa.

Elliptic Curves¶

• Fixed a few places where calling LFunction on an elliptic curve might reassign the generator names of already-existing polynomial rings. Reported by D. Angdinata.

Groups¶

• A situation where Order applied to infinite matrix groups defined over characteristic zero fields incorrectly returned a finite order has been fixed. Reported by S. Waldron.
• A long-standing bug in defining a pc-group using a power-commutator presentation has been resolved. The bug was reported by D. Roe as a bug in SmallGroupDecoding.
• A problem with matrix group element centralizer computation has been fixed. Bug reported by M. Grassl as a crash in GroupName.
• A complaint about computing the automorphism group of a 01 matrix has been resolved. Reported by M. Grassl.

Lattices¶

• A crash in IsGLZConjugate involving short vector enumeration has been fixed. Reported by K. Andersen.

Representation Theory¶

• A crash in CompositionSeries for modules with trivial action and in characteristic zero has been fixed. Reported by L. Scheeren.