TDA4j 0.6.0

What's Changed

• tutorial-2026-10-16 by @michiexile in #44
• tutorial-2026-10-16 by @michiexile in #45
• Ccr 66e09665 8g203t by @michiexile in #46
• Release workflow: trigger on v* tags only, reject non-version refs by @michiexile in #47
• Release workflow: attach the release to the dispatched tag, never the branch by @michiexile in #48
• Cubical speed-up, open library, tda4j-plot, category nerves and Brown's collapse, chunks union-find fixes by @michiexile in #49
• Developer's guide catch-up, plots in the core, Mermaid, and project practices (issues, changelog, CI jar, format hook, coverage, Dependabot) by @michiexile in #50
• Deps: Bump actions/setup-java from 5 to 6 by @dependabot[bot] in #70
• Deps: Bump the libraries-and-plugins group with 6 updates by @dependabot[bot] in #71
• Deps: Bump actions/upload-artifact from 4 to 7 by @dependabot[bot] in #72
• Coverage: send the weekly report to Codecov by @michiexile in #73
• Make NaN the cubical mask: a NaN pixel is not in the complex by @michiexile in #74
• Plots from MATLAB and the CLI, and saved results (#63) by @michiexile in #77
• First pass at developer guide documentation by @michiexile in #78
• Enhance release workflow with tag validation by @michiexile in #85

New Contributors

• @dependabot[bot] made their first contribution in #70

Full Changelog: v0.5.0...v0.6.0

TDA4j 0.5.0

What's Changed

• Fix release.yml's asset globs for the now-lowercase project name by @michiexile in #24
• RELEASE.md: credentials come from ~/.sbt/sonatype_credentials, not en… by @michiexile in #25
• Serialize gh-pages publishes between docs.yml and release.yml by @michiexile in #26
• Fix invisible header logo and chunky menu/breadcrumb highlights by @michiexile in #27
• Fix landing-page.md placement per Laika's documented mechanism by @michiexile in #28
• Add .default-version override for the docs site's root redirect by @michiexile in #29
• Fix ux.js patch to cover laikaPreview, not just laikaSite by @michiexile in #30
• Rename BarcodeContext to BarcodeBuilder; correct docs on sc:compile, TDAlab re-exports, built-in Sonatype by @michiexile in #31
• Reduce noisy output in CLI and other interfaces, some housekeeping by @michiexile in #32
• Tutorials with MATLAB tabs and docs-as-tests; Sage-parity simplicial sets; public complex objects; persistent group homology by @michiexile in #33
• CI: cancel superseded PR runs, parallel test/docs/mima jobs, stricter lint; PR template; fix lint on scala by @michiexile in #34
• Docs deploy: publish the site at the gh-pages root and clear stale files by @michiexile in #35
• Flatten the core package, consolidate simplicial sets, and implement the API audit by @michiexile in #36
• Fix PackedRipserCohomologyEngine infinite loop on asymmetric distance data by @michiexile in #37
• Persistence defaults (H0-H2, no zero-length bars), cycles or cocycles from every engine, faster generic cohomology, docs audit by @michiexile in #38
• Dense cell numbering in CellularCohomologyEngine (cohomology and its cycles step) by @michiexile in #39
• Paper groundwork: faster VR, fast engines and Helix alpha; alpha radius dispatch; correctness fixes; benchmark harness by @michiexile in #40
• Add a Bowyer-Watson alpha backend with exact predicates (default up to 4-D) by @michiexile in #41
• Read distance matrices' lower triangle; benchmark the alpha backends by name; paper plan update by @michiexile in #42
• Large point clouds: clifford50000 crash fix, neighbour lists, primitive engine state by @michiexile in #43

Full Changelog: v0.4.0...v0.5.0

Added improved Alpha shapes algorithm

The Helix algorithm for alpha-shapes added to the codebase.

TDA4j v0.1.1

Basic functionality developed. After several false starts, and with help from the Spring 2026 TDA class at the CUNY Graduate Center, especially thanks to @jessedimino, @keikebreau and @trevorgor289, some issues with resolving given statements were finally cleared up.

Barcode algebra remains stable.
Persistent homology computations now possible, with the Clear&Compress optimizations implemented by @keikebreau and @trevorgor289.

Library still is extensively in flux

First very partial fragments of a library

We are building a replacement for JavaPlex - named TDA4j. In this current alpha release, we have:

1. Preliminary infrastructure and scaffolding for a persistent homology library.
2. Infrastructure and capacity for computing images, kernels and cokernels for maps between persistence modules based on known barcode decompositions and matrices representing the maps.

We do not yet have most of the things we expect to include in the library - including comprehensive documentation, support for computing persistent homology (and cohomology) with or without explicit representatives, careful API exposed to enable using the library from Matlab, tutorials adapted from the JavaPlex tutorials to the new design choices in this library et.c.

This is a very early pre-release. This is in no way a finished product - this is work in progress, and almost everything in the library may change before we arrive at a first official release.