Magma V2.22-4 Patch Notes
Patch release for Magma V2.22-4. Updated areas: Algebraic Function Fields, Coding Theory, Commutative Algebra, Cubic models of curves, Dedekind Modules and 9 more.
Algebraic Function Fields
The algorithm choice for computing a 2-element representation of an ideal has been improved. Reported by R. Granger.
Coding Theory
The function
ExtendCodehas been restored (accidentally only available asExtendCodeFieldpreviously). Issue reported by D.W.C. Kuijsters.
Commutative Algebra
Some operations with of fields of fractions of affine algebras have been sped up. Related crash (now fixed) reported by T. Ikuta.
A bug in factoring polynomials over polynomial quotient rings over finite fields (which are themselves finite fields) has been fixed. Reported by A. Sutherland.
A problem with linear factors in reducible polynomials has been fixed. Reported by A-S. Elsenhans.
Crashes in Groebner basis computation over the rational field has been fixed. Reported by A-S. Elsenhans.
Cubic models of curves
A crash with
PointSearchfor cubic models has been fixed.
Dedekind Modules
A crash involving Dedekind modules has been fixed. Reported by V. Kliuchnikov.
A crash when constructing a Dedekind module of degree 0 has been fixed. Reported by M. Kirschmer.
Finite Fields
A crash when trying to compute a logarithm in a large finite field for which the data is not available has been fixed. Reported by M. Tillinghast.
Graphs
Using
'in'to test whether a set or sequence of vertices is in the edge set of a graph now returns false instead of raising an error when there is no corresponding edge.
Group Characters
A crash in the group characters code has been fixed. Bug report from Matthieu Rambaud.
The intrinsic
Basiswhen applied to a character ring now uses the defaultCharacterTablealgorithm, instead of always going to the Dixon-Schneider algorithm.
Groups
Calls to the
ASpfunctions now trap odd dimensions to give a runtime error. Bug reported by T. Dokchitser.A crash when computing projective classical groups over a large finite field has been fixed. Bug reported by T. Dokchitser.
Incorrect construction of some low dimensional
PGOgroups fixed. Bug reported by T. Dokchitser.Dimension lower bounds on the
Spin,SpinPlusandSpinMinusintrinsics are all now 4. This fixes a crash reported by T. Dokchitser.The order assigned to
PSigmaU(2,q), when q = 3 mod 4, has been corrected. Bug reported by T. Dokchitser.An improved access function for a single
SmallGroupof order p^7 (p >= 7) is included. Request of E. O’Brien.
Hyperelliptic curves
A longstanding bug with point counts on genus 1 hyperelliptic curves has been fixed (the twisting parameter was applied twice). Reported by E. Howe.
Lattices
A crash with
BKZwhen the number of columns exceeded the rank was fixed. Reported by A.-S. Elsenhans.
Matrix Algebras
A bug involving the wrong element type when iterating over a matrix lie algebra has been fixed. Reported by J. Maglione.
Numerical Linear Algebra
A problem with images of complex matrices was fixed.
Sparse Matrices
A missing error check has been added to
Nullspaceapplied to sparse matrices over rings which are not supported. Reported by D. Yasaki.