Magma V2.23-8 Patch Notes

Galois Groups¶

• The computation of subfields and Galois groups was improved by a refined cycle type analysis.
• An infinite loop has been broken in the computation of a prime, which does not divide the discriminant of the defining polynomial of any subfield, to use in the computation of a Galois group of a polynomial over a function field. Reported by R. Müller.

Graphs¶

• The MaximumMatching of an edgeless graph no longer crashes.

Hyperelliptic Curves¶

• A possible crash when trying to make sequences of tuples containing points from incompatible hyperelliptic curves has been fixed.

Lattices¶

• Some difficulties with spinor genera have been fixed by M. Kirschmer. The problems arise from differences between the notion of Cassels (thus Conway-Sloane) of "spinor genus", which is more often called the proper spinor genus. The SpinorGenerators intrinsic now has a Proper vararg (by default true) to help with issue, but a more complete overhaul is still necessary. Reported by A. Haensch.
• The Genus intrinsic now properly considers denominators.

Linear Systems¶

• A crash in the application of the PolynomialMap of a Linear system to a sequence of vectors has been fixed.

Local Fields¶

• A bug with Coordinates over the p-adics was fixed. Reported by A. Rahm.
• A bug in testing whether a polynomial is inertial has been fixed.

Polynomial Rings¶

• A problem with denominator handling with mulvariate polynomials defined over relative number fields has been fixed. Reported by M. Grassl.
• Some problems in computing complex roots of real polynomials have been fixed. Reported by E. Sertoz and J. Jones.
• Fixed a crash when finding the variety of an ideal via exhaustive search, arising when there were no points in the variety.
• A missing error check has been included to ensure that divisors are non zero when using div.