Patch Notes

Magma V2.12-17 Patch Notes

Patch release for Magma V2.12-17. Updated areas: Algebraic Geometry, Character Theory, Elliptic Curves, Finite Fields, Function Fields and 6 more.

11 areas

Algebraic Geometry

Character Theory

  • A bug in the CharacterTable function has been fixed. This bug afflicted the IR algorithm for some groups. Bug reported by Derek Holt.
  • A bug where the character table of a p-group could be printed as an ordinary sequence of characters has been fixed.

Elliptic Curves

  • A bug arising from isomorphisms between schemes that happen to be elliptic curves has been fixed. These were sometimes wrongly treated as isomorphisms on the point groups, leading to crashes.
  • The composition of a scheme map and an isogeny is now created as a scheme map.

Finite Fields

  • A new Conway polynomial for $(2, 86)$ has been added.

Function Fields

  • A bug in determining whether an element of a non-simple extension of an algebraic function field is a constant has been fixed.

Groebner Bases

  • A bug in GroebnerBasis, which was returning wrong answers over prime finite fields of size about $2^{25}$, has been fixed. Reported by D. Rusin.

Groups

  • The function Characteristic incorrectly allowed arbitrary matrix groups as input. This has been corrected to restrict the function to matrix groups over finite fields only.
  • Memory leaks related to matrix group conjugacy class operations have been fixed. Bug reported by Derek Holt.
  • A bug which caused computation of conjugacy classes of a permutation group to crash has been fixed. Bug reported by Gabriele Nebe.

Incidence Structures

  • A bug in Residual (of a symmetric 2-design with respect to a block) that caused the value of $t$ for the resulting design to drop to zero has been fixed. Bug reported by Bernardo Rodrigues.

Linear Algebra

  • A leak in the function Rank when applied to a matrix over a number field has been fixed. Reported by D. Holt.

Number Fields

  • The internal precision used for the evaluation of the units during the class group computation has been increased. This should make the error, "precision error in unit computation", much less likely.

System

  • A bug in which using the '%h' modifier would cause the incorrect printing of objects following the modifier in printf statements has been fixed.
  • Various bugs in ProfileReset and SetProfile have been fixed.