--- title: "Magma V2.12-17 Patch Notes" canonical: "https://docs.magma-maths.org/patchnotes/2.12-17.html" source: "https://docs.magma-maths.org/patchnotes/2.12-17.md" --- # Magma V2.12-17 Patch Notes ## Algebraic Geometry - Bugs in `Divisor``(C,I)` and `Place``(C,I)` have been fixed. ## 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`](../Combinatorics/Designs/operation.md#function-residual-inc-incblk) (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`](../MagmaLanguage/TheMagmaProfiler/profiler-basics.md#function-profilereset) and [`SetProfile`](../MagmaLanguage/TheMagmaProfiler/profiler-basics.md#function-setprofile-boolelt) have been fixed.