1.7.1

This is a minor release with some changes related to forthcoming changes in GAP. These changes were implemented by Fabian Zickgraf @zickgraf.

1.7.0

This is a minor release with some new features, and some other improvements in code quality.

What's Changed

• Change test that relies on xpdf not being installed by @mtorpey in #578
• DigraphAbsorptionProbabilities by @mtorpey in #548
• Fix test files: strings and unbinds by @mtorpey in #579
• Add immediate methods for connected and strongly connected graphs by @mtorpey in #583
• kernel: fix mem leaks for permutations allocated but not freed by @james-d-mitchell in #589
• Remove references to bin/gap.sh by @fingolfin in #597
• Fix prototype warnings by @fingolfin in #598
• Added EdgeWeightedDigraph by @RaiyanC in #575
• Add AbsorptionExpectedSteps by @mtorpey in #585
• Fix a typo by @fingolfin in #608
• configure.ac: fix bashism in string equality test by @orlitzky in #613

1.6.3

This is a minor release with some bug fixes, and other issues resolved:

• There was a minor bug in the RandomDigraph method for IsEulerianDigraph, resolved by @mtorpey
• Joe Edwards and Maria Tsalakou were incorrectly listed as authors resolved partially by @james-d-mitchell in #576
• Standardise the way that UndirectedSpanningForest works in relation to mutability by @wilfwilson in #582
• Add immediate methods for connected and strongly connected digraphs by @mtorpey
• There was a minor memory leak in the kernel extension resolved by @james-d-mitchell

1.6.2

Changes in this release

• PackageInfo.g: link to Mathjax manual by default by @fingolfin in #554
• PackageInfo.g: link to Mathjax manual by default by @fingolfin in #558
• ci: change master to main on azure by @james-d-mitchell in #567
• Rewrite buildsystem to use Makefile.gappkg by @fingolfin in #566
• Update two M4 files, correct a comment by @fingolfin in #568
• Fix some typos found by codespell by @fingolfin in #569
• Use same URL as in my other packages by @olexandr-konovalov in #572
• Avoid src/ prefix for GAP headers by @fingolfin in #571

1.6.1

This is a minor release fixing a number of minor issues:

• Use compiled.h instead of src/compiled.h by @fingolfin in #560
• Fix tourn decoder by @james-d-mitchell in #559
• Change CayleyDigraph to use AsSet by @fingolfin in #564

1.6.0

This is a minor release including a number of new features:

• Implement IsPermutationDigraph by @baydrea in #513
• Add more implications (including some implications of falsity) by @wilfwilson in #494
• Add OnTuplesDigraphs and OnSetsDigraphs by @wilfwilson in #449
• Add checks for upper/lower semimodular lattices by @james-d-mitchell in #375
• Add AsDigraph for partial perms by @james-d-mitchell in #526
• Add DigraphRandomWalk by @mtorpey in #543
• Add constructors for random digraphs with particular properties by @KamranKSharma in #531
• Add LatticeDigraphEmbedding method by @MTWhyte in #538
• Add IsDistributiveLatticeDigraph property by @MTWhyte in #528

The following improvements were also made:

• Make improvements to IsMeetSemilatticeDigraph and IsJoinSemilatticeDigraph by @MTWhyte in #556
• Add a workaround for macOS code signing issues by @fingolfin in #555

1.5.3

What's Changed

• digraph: fix String method for chains/cycles by @james-d-mitchell in #542
• Disable edge labels if not already set in some cases by @james-d-mitchell in #540
• build: remove the default flag -march=native by @james-d-mitchell in #541
• doc: fix typos by @james-d-mitchell in #544
• Update version numbers etc for 1.5.3 by @james-d-mitchell in #547

Full Changelog: v1.5.2...v1.5.3

1.5.2

What's Changed

• More fixes for loading grape after digraphs by @fingolfin in #535

Full Changelog: v1.5.1...v1.5.2

1.5.1

What's Changed

• Remove vertex labels when performing edge union by @Joseph-Edwards in #507
• Remove doc/*.js, doc/*.css, doc/chooser.html from the repo by @wilfwilson in #511
• DigraphAddEdge: do not add an edge label if edge labels are not yet initialised by @wilfwilson in #509
• kernel: fix check in OutNeighbours by @james-d-mitchell in #519
• Fix compatibility with grape by @fingolfin in #530

New Contributors

• @Joseph-Edwards made their first contribution in #507

Full Changelog: v1.5.0...v1.5.1

1.5.0

This is a fairly major release of the Digraphs package, containing some bugfixes and several new features.

In this version, we welcome Finn Buck, Tom Conti-Leslie, Ewan Gilligan, Lea Racine, and Ben Spiers as contributors to the package.

Bugfixes

• The edge labels of Cayley digraphs could sometimes be incorrect (Fixed by Jan De Beule in PR #452)
• Typos in the documentation of IsDirectedTree and an error message for OnDigraphs were fixed (Wilf A. Wilson in PRs #480 and #498)

A database of one-off named graphs and digraphs, and more families of standard examples

We especially wish to highlight the greatly expanded functionality for creating digraphs that are either famous one-off examples, or are part of a family of standard examples.

In particular, Finn Buck, Lea Racine, James D. Mitchell, Marina Anagnostopoulou-Merkouri, and Ben Spiers implemented functions to construct many more families of standard examples (currently documented in Section 3.5), which were added in in PRs
#408, #409, #411, #415, #416, #417, #423, #424, #425, #445, #454, #456, and #490.

Furthermore, Reinis Cirpons, Tom Conti-Leslie, and Murray Whyte added a database of one-off named graphs and digraphs in PR #404.
These digraphs can be constructed by calling Digraph with a string of appropriate name, e.g. Digraph("brinkmann").
The available names can be accessed with the ListNamedDigraphs function.

Other new features

• Tarjan and Lengauer's almost-linear time dominators algorithm was implemented, and is available via Dominators and DominatorTree (James D. Mitchell, Marina Anagnostopoulou-Merkouri, Samantha Harper, and Finn Buck, in PR #336)
• MaximalCommonSubdigraph and MinimalCommonSuperdigraph were introduced (Luke Elliot, PR #361)
• DigraphShortestPathSpanningTree was introduced (Jan De Beule and Wilf A. Wilson, in PR #363)
• Lawler and Byskov's algorithms for chromatic number were implemented (Ewan Gilligan, PR #382)
• Cayley digraphs now have pre-set vertex and edge labels (Jan De Beule and Wilf A. Wilson, in PR #385)
• DigraphCycle was added as a synonym for CycleDigraph (Wilf A. Wilson, PR #441)
• Several new digraph product operations were introduced: StrongProduct, ConormalProduct, HomomorphicProduct, and LexicographicProduct (Finn Buck, PR #460)
• The operation IsDigraphPath was introduced (James D. Mitchell, PR #489)

Other changes

• The ViewString and inherently known properties of trees, forests, cycle digraphs and tournaments were improved (Wilf A. Wilson in PRs #440 and #447)
• Some technical changes to the package were made by James D. Mitchell in PR #488 and by Max Horn in PR #502