Magma V2.19-8 Patch Notes

Algebraic Function Fields¶

• The prime selection when computing GaloisGroups of polynomials over function fields of prime characteristic has been improved.
• The computation of transformations in one place of the Galois group computation for reducible polynomials has been improved to avoid infinite loops.

Commutative Algebra¶

• Some bugs in PrimaryDecomposition and Radical involving ideals with graded orders have been fixed.

Curves¶

• A bug in the arithmetic and construction of automorphisms in the curve automorphism group machinery has been fixed. Reported by J. Rouse.
• A bug in the preimage of a map between a function field of a curve and its representation as an algebraic function field has been fixed. Reported by J. Rouse.
• A bug in the conversion of function field places to curve places in WeierstrassPlaces of a divisor of a curve has been fixed. Reported by M. Derickx.

Integer Factorization¶

• A problem with not detecting powers when stored factors were used has been resolved. For instance, $pq^2$ where $p$ was stored, and $q$ large, say $p$ is $10^{15} + 37$ and $q$ is $10^{50} + 151$.

Matrices¶

• Some crashes involving huge matrices over medium prime finite fields have been fixed.

Orders and Algebraic Fields¶

• Fixed a possible crash in IsPrincipal calculations applied to order ideals.
• A few fixes supplied by J. Kl{ü}ners have been made to GaloisGroup computations.
• A fix has been made to CharacteristicPolynomial so that properties of related orders are not altered during the computation. Reported by E. Thome.

System¶

• The Intel 64 AVX version has been sped up for several types of Groebner basis and linear algebra computations (up to 1.5 times faster in some cases).
• User-defined types may now define a Compare intrinsic that will be used by system sorting operations.