---
title: "Magma V2.22-5 Patch Notes"
canonical: "https://docs.magma-maths.org/patchnotes/2.22-5.html"
source: "https://docs.magma-maths.org/patchnotes/2.22-5.md"
---

<a id="magma-v2-22-5-patch-notes"></a>
# Magma V2.22-5 Patch Notes

## Aggregates

- An intrinsic `Components` has been added for cartesian products.

## Algebraic Function Fields

- An infinite loop in the `GaloisGroup` and `Subfields` computations for an algebraic function field defined as an extension of another algebraic  function field by a polynomial with denominators has been stopped.  Reported by R. Müller.

## Algebraic Number Fields

- A sequence with universe the number field of an order will no longer be coerced (if possible) into an element of the order when given as the RHS of the `ext<O| >` or `ideal<O| >` constructors. Reported by E. Thóme.
- `IsRootOfUnity` was completely wrong for the case of cyclotomic fields using the sparse representation. Reported by T. Dokchitser.
- `Norm(f)` for a univariate polynomial f with coefficients in a field extension was wrong in general.  Reported by J. Klueners.
- `HilbertSymbol` for number fields and prime ideals over 2 has been sped up considerably.  Due to M. Kirschmer.

## Coding Theory

- The [`AdditiveCode`](../CodingTheory/AdditiveCodes/creation.md#constructor-constructor-additivecode-fldfin-rngintelt-list-code) constructor that takes a linear code as input now ensures it is defined over a field.
- A problem with automorphisms of codes over Z/4Z was fixed.

## Lattices

- The `NaturalAction` vararg for `IsIsometric` of totally definite number field lattices has had its restriction about ambient inner products removed. Noted by M. Kirschmer.
- A bug in the `AutomorphismGroup` function has been fixed. The bug was reported by M. Kirschmer.

## Local Fields

- An ancient problem with `Factorization` over the p-adics was fixed. The problem was that a incorrect test was being used to test for squarefreeness of an auxiliary polynomial (the discriminant was used, when this could be 0 to the ambient precision without the polynomial itself having a repeated factor). This would cause occasional infinite loops. Reported by T. Dokchitser and J. Jones.

## Modules

- Some bugs in `IsIsomorphic` for G-modules over the rational field have been fixed.  Reported by C. Fieker.

## Series Rings

- An improvement has been made to finding the roots of a polynomial over a series ring over a local field.

## System

- [`Split`](../MagmaLanguage/InputOutput/string.md#function-split-monstgelt-monstgelt) no longer produces an empty first item if the string begins with a separator and `IncludeEmpty` is false (which is the default).  Reported by T. Dokchitser.