Change log for Magma V2.28-19 (Released 21/2/2025)

Associative Algebras

·Bug in the choice of representatives in Neighbors for quaternion ideals has been corrected.

Curves

·UniformizingParameter for points and places on a curve has been improved to return smaller elements. Reported by Maarten Derickx.

Finite Fields

·A crash in Embed involving a mixture of default and non-default finite fields has been fixed. Reported by Yusuke Uesato.

Graphs

·OpenGraphFile will now raise an error when the file cannot be opened or is otherwise invalid. Formerly it would print a message and return an unusable IO object. Reported by Primoz Potocnik.

Groebner Bases

·Some bad slowdowns in Groebner basis computation over Z or Q (when units are present) have been fixed. Reported by Raymond van Bommel.

Group Algebras

·Error checking for quo<|> has been increased to ensure that vector representation is being used. Reported by Joseph Baine.

Groups

·An updated version of MinimalDegreePermutationRepresentation has been supplied by Derek Holt.

·An error in NumberingMap for permutation groups has been fixed. This bug may have caused incorrect answers to be returned when using the NumberingMap. Bug reported by Primoz Potocnik.

·A crash in classical matrix group recognition has been fixed. This was reported as a crash in testing two p-groups for isomorphism by Primoz Potocnik and Eamonn O'Brien.

Hilbert Modular Forms

·Fixed bug in InnerProduct, checking for an unassigned local variable. Reported by Edgar Costa.

Hyperelliptic Curves

·Extra precision in the computation of Conductor has been allowed. Reported by Robin Visser.

Linear Codes

·A very bad slowdown when creating a large number of linear or additive codes has been fixed. Reported by Markus Grassl.

Local Rings

·SeriesPrinting for local rings has been improved. Reported by Rob de Jeu.

Modular Forms

·Fixed bug in creation of spaces of modular forms with character, when the codomain of the character is not minimal. Reported by Lewis Combes.

System

·A new parameter ExitSummary has been added to Fork (default false) so that, if selected, child processes created by Fork print the exit summary ("Total time...") when Magma exits; by default that summary is now suppressed. Also, new intrinsics SetExitSummary/GetExitSummary allow one to set/get a flag which determines whether Magma prints the exit summary (true by default at startup). Requested by Drew Sutherland.

·An occasional crash in the interpreter when recovering from a runtime error during a try/catch statement has been fixed.