---
title: "Magma V2.21-12 Patch Notes"
canonical: "https://docs.magma-maths.org/patchnotes/2.21-12.html"
source: "https://docs.magma-maths.org/patchnotes/2.21-12.md"
---

<a id="magma-v2-21-12-patch-notes"></a>
# Magma V2.21-12 Patch Notes

## Algebraic Function Fields

- Error checking for non simple fields in intrinsics using Cartier representation has been improved.
- Printing of elements of non-simple fields has been fixed in some cases. Problem reported by M. Grassl.

## Elliptic Curves

- A glitch (runtime error in some examples) in elliptic curve `Chabauty` has been fixed.  Reported by B. Naskrecki.

## Group Algebras

- A bug in scalar multiplication in group algebras in the presence of zero divisors has been fixed.  Reported by U. Thiel.

## Hyperelliptic Curves

- The functions `Points` and `jPoints` for point search on Jacobians of hyperelliptic curves now have an optional parameter `ReturnAll`.  When true, the functions return all points found in the search, including any larger than the height bound.
- Minor problems (causing runtime errors in a couple of examples) have been fixed in `TwoCoverDescent`.  Reported by A. Sutherland.
- A bug in `Degree3Subcovers` has been fixed.

## Noncommutative Groebner Bases

- A bug involving the final interreduction of a noncommutative Groebner basis when a degree bound is present has been fixed. Reported by J. Blasiak.

## Number Fields

- The sieve algorithm used inside `ClassGroup` is now always switched off for fields of degree $6$ (and higher), in order to avoid crashes.  (One example was reported by A. Joux and A. Gelin.)
- `PicardGroup` now accepts fields of type `FldQuad`.

## Polynomials

- A bug causing an incorrect result when powering extremely high degree binary polynomials in quotient rings has been fixed. Reported by R.P. Brent.

## System

- A potential crash in the profiler has been fixed; it could arise when the return type of an intrinsic was invalid.  Reported by W. B. Ladd.