Magma V2.28-9 Patch Notes

Algebraic Function Fields¶

• RationalFunction for elements of non simple function fields now ensures the element has known coefficients rather than returning 0. Reported by F. Hess.
• Applying Automorphisms to elements with a product representation no longer computes coefficients of the element.
• Taking preimages of the identity automorphism has also been fixed. Reported and fixed by F. Hess.

Algebraic Number Fields¶

• Fixes have been made to recent improvements in MaximalOrder computations. Reported by J. Schleucher.
• Decomposition of finite places of coefficient fields in extensions has been enabled. Reported by J. Schleucher.

Arithmetic Geometry¶

• Some fixes have been to the package which computes invariants or twists of genus 3 curves. Supplied by R. Lercier.
• Fixes have been made in the code for determining a bound for the difference between naive and canonical height on genus 2 Jacobians. Fix supplied by M. Stoll and S. Muller.

Galois Groups¶

• Precision handling has been improved in SplittingField so that the valuation of the discriminant can be accurately determined. Reported by J. Schleucher.
• User provided primes using the Prime parameter to GaloisGroup are now checked to be unramified. If a user given prime is ramified, another prime will be selected for the computation. Reported by J. Schleucher.

Lie Algebras¶

• A crash in Algebra applied to a universal enveloping algebra has been fixed. Reported by E. Assaf.

Local Fields¶

• Increased error checking of the map given as the second argument to RelativeField is now done. Reported by J. Schleucher.

Permutation Groups¶

• Computing the quotient of permutations groups by quo``<G|N> where $N$ is the trivial subgroup has been fixed so that the result is the degree reduction of $G$ (consistent with previous behaviour).