---
title: "Magma V2.21-2 Patch Notes"
canonical: "https://docs.magma-maths.org/patchnotes/2.21-2.html"
source: "https://docs.magma-maths.org/patchnotes/2.21-2.md"
---

<a id="magma-v2-21-2-patch-notes"></a>
# Magma V2.21-2 Patch Notes

## Coding Theory

- [`ConstaCyclicCode`](../CodingTheory/LinearCodes/families.md#function-constacycliccode-rngintelt-rngupolelt-fldfinelt) is more efficient now, particularly for long codes where the constant has large order.  Reported (and fixed) by M. Grassl.

## Commutative Algebra

- A crash in `PrimaryDecomposition` over function fields has been fixed.  Reported by M. Stoll.

## Groups

- The new `Group` intrinsic did not operate correctly when given strings with “SU” involved. Similarly, “U” has been included as a synonym for “PSU”.

## Multivariate Polynomials

- The deprecated parameter `Digits` has been removed from the `Variety` and [`VarietySequence`](../CommutativeAlgebra/PolynomialRingIdealOperations/variety.md#function-varietysequence-rngmpol) intrinsics.

## Number Fields

- A problem with `HeckeCharacterGroup` of an abelian extension was fixed, taking into account infinite places.
- The `Extend` intrinsics for Dirichlet and Hecke characters (and groups) have been modified to eliminate the extraneous second return value (there is not really a kernel involved). The `Extend` intrinsic for groups thus now returns a group of the same size.
- The application of an automorphism to a fractional ideal of an order of a quadratic field has been fixed. Reported by M. Kirschmer.
- The error checking in `LLL` and [`LLLBasisMatrix`](../LatticesQuadraticForms/Lattices/reduction.md#function-lllbasismatrix-lat) when the input is an ideal of an order of a number field has been improved to give a runtime error when the number field is not a direct extension of the rational field.
- A problem with `MinimalPolynomial` was fixed, when the polynomial that was found had degree 0 (and thus trivial factorisation).

## Schemes

- Projective points with coordinates in Euclidean domains are now more strictly checked and as a result some points which have previously been able to be constructed are no longer able to be constructed.

## System

- Using sequence indexing on large strings (greater than 2GB) now works properly.
- `Read` has been slightly sped up for larger files.
- Some unnecessary memory duplication when calling [`eval`](../MagmaLanguage/StatementsAndExpressions/eval-expression.md#literal-literal-eval-eval-expression) has been removed.

## Topology

- Printing of objects of type `SmpCpx` has been fixed. Reported by K. Joanidis.

## Vector Spaces

- An incorrect answer has been fixed for the function `ExtendBasis`. Reported by R. Zeier.