3.4.1

This is a minor release including some bugfixes and improvements. The required minimum version of libsemigroups is increased from v1.1.0 to v1.3.2. The required version of Digraphs is increased to v1.2.0. The datastructures package was implicitly required (via Digraphs), and now at least version v0.2.5 is required explicitly. The version of GAP required was implicitly at least v4.10.0, but was explicity v4.9.0, it is now explicitly v4.10.0.

3.4.0

This is a minor release with the following new features added to the package:

• CanonicalReesMatrixSemigroup and CanonicalReesZeroMatrixSemigroup written by Chris Russell.
• ParseRelations for finitely presented semigroups or monoids written by Luke Elliott.
• TikzString method was implemented for collections of PBRs by Finn Smith.

The following bugs/issues were resolved:

• Issue #685: after some somewhat recent changes in libsemigroups some infinite finitely presented semigroups in GAP reported their size as being -2. Fixed by James D. Mitchell.
• Issue #680: Semigroups did not compile with recent git versions of libsemigroups. Reported by Wilf A. Wilson fixed by James D. Mitchell.

The required minimum version of libsemigroups is now v1.1.0.

3.3.2

This is a very minor release fixing the following issues.

• Issue #676 and Issue #677 reported by Reinis Cirpons, where for some congruences NonTrivialCongruenceClasses failed to work, but CongruenceClasses did work. This was caused by an issue in EquivalenceRelationPartition; resolved by James D. Mitchell.

• An issue in the equality, less than, and product methods for PBRs which previously permitted PBRs of different degrees to be given as arguments, resulting in unhelpful errors from within the implementations of these methods; resolved by James D. Mitchell.

3.3.1

This is a minor release fixing some issues in the build system Max Horn related to compatibility with future versions of GAP, and some other minor fixes by James D. Mitchell and Wilf A. Wilson.

3.3.0

This is a minor release fixing some issues in the build system Chris Jefferson, some improvements to the isomorphism capabilities of the package James D. Mitchell, and the introduction of a rudimentary function to compute the automorphism group of an arbitrary semigroup. From v3.3.0, the Semigroups package requires the images package version 1.3.0 or higher.

3.2.5

This is a minor release to fixing some build issues for windows [Chris Jefferson] and fixing an issue in IsRowTrimBooleanMat, IsColTrimBooleanMat, and IsTrimBooleanMat [Finn Smith] see Issue #654 for more details.

3.2.4

This is a minor release to fix a memory leak and some other issues in the kernel module.

3.2.3

This is a minor release to make some changes fo compatibility with the Digraphs package v1.1.1 and GAP, and to fix a memory leak in the kernel module.

3.2.2

This is a minor release to update the version of libsemigroups to v1.0.5, to include some changes for compatibility with GAP, and to fix the following issues

• Issue #632 where file objects were not closed properly if an error was given;
• Issue #636 the compiler flag -march=native is only added if it is supported by the compiler;
• Issue #637 where IsomorphismPermGroup sometimes returned an incorrect answer.

The changes in this release were made by Max Horn and James D. Mitchell.

3.2.1

This is a minor release to update the version of libsemigroups to v1.0.2,
and to include some changes for compatibility with GAP The changes in this
release were made by James D. Mitchell and Wilf A. Wilson.