Magma V2.24-2 Patch Notes

Coding Theory¶

• A crash in IsPure for quantum codes has been fixed.

Coherent Sheaves¶

• The saturation process for coherent sheaves, as used internally and explicitly through SaturateSheaf, has been fixed. The error caused the full module computed for the sheaf to be too large in some cases. (Fix added in the initial V2.24 release).

Commutative Algebra¶

• The algorithm to compute radicals of multivariate polynomial ideals of positive dimension has been greatly sped up for a large class of inputs. Problem instance provided by M. Reid.

Curves¶

• A crash when constructing places from a point on a curve has been fixed.
• A bug has been fixed in the Shanks group order routine, used in some cases to compute the order of the Jacobian of a hyperelliptic curve over a finite field. This could cause either crashes or wrong answers. Reported by E. Gonzalez Jimenez.
• The incorrect setting of the GeometricallyIrreducible attribute when setting the IsNonsingular attribute on an affine curve has been fixed.

Elliptic Curves over Function Fields¶

• A bug with computing the MordellWeilGroup when the order of the torsion group was not coprime to the extension degree of the field of the geometric rank was fixed. Reported by A. Landesman.

Function Fields¶

• The computation of the norm of some elements having product representation with negative exponents has been fixed.
• Coercion between equal non-simple orders has been fixed.

Galois Groups¶

• The computation of Galois groups over Number Fields was improved by using the discriminants of subfields.
• Precision computations when considering a subfield have been improved. Reported by S. Marseglia.

Invariant Theory¶

• A hang in FundamentalInvariants applied to certain invariant rings has been fixed. Reported by U. Thiel.

L-Series¶

• A crash from an empty array in the internal GammaSeries has been fixed.

Lattices¶

• Various lattice functions involving integral lattices (such as enumeration) now use information about the evenness of a lattice when applicable. Noted by M. Kirschmer and G. Nebe.

Lie Theory¶

• A crash when comparing elements of Lie algebras with elements of vector spaces has been fixed.

Modular Symbols¶

• A crash in NewformDecomposition involving very large number fields has been fixed. Reported by A. Sutherland.

Module Theory¶

• The function IsSelfDual has been added for KG-modules.
• The Meataxe algorithm has been improved in the case that the result quotient module has large dimension.

Number Fields¶

• Coercion between equal non-simple orders has been fixed.

Profiler¶

• A crash that prevented use of the profiler has been fixed.

Real Numbers¶

• The deprecated LinearRelation intrinsic now accepts sequences and vectors over the reals. Noted by D. Kohel.

Series Rings¶

• A crash in the Sqrt computation of a series over a non-field has been fixed.
• Error checking has been improved in ensuring that unramified extensions are constructed only from inertial polynomials. Reported by N. Müller.

System¶

• The exit (and quit) directive can now take an argument giving the desired exit status.