v0.9.0

fa2 v0.9.0 — Modernized for Python 3.9-3.14, NetworkX 3.x, Cython 3.x

The first major release in 5+ years. Complete modernization while maintaining full backward compatibility with v0.3.x.

New Features

• linLogMode: Logarithmic attraction F = log(1+d) for community detection (verified against Gephi source + paper)
• seed parameter: Reproducible layouts via seeded RNG
• callbacks: Iteration hooks for animation and convergence monitoring
• NetworkX 3.x support (also works with 2.7+)
• igraph support: Robust handling of weighted, edgeless, and directed graphs

Algorithm Fixes

• Fixed strongGravity axis bug (and → or — nodes on axes were silently skipped)
• Fixed logAttraction formula (was missing log(1+d) term)
• Fixed Barnes-Hut leaf double-repulsion (now uses one-sided force, matching Gephi reference)
• Fixed Region single-node mass center calculation
• Added ZeroDivisionError guards in speed adjustment

Code Quality

• assert → proper ValueError/TypeError with helpful messages
• Parameter validation on all numeric inputs
• Input validation: symmetry (dense + sparse), pos shape, self-loop warning, directed graph rejection
• Type hints on all public API methods
• 112 tests, 100% coverage on forceatlas2.py

Build & Compatibility

• Python 3.9–3.14 supported
• Cython 3.x build via .pyx (replaces old .pxd approach)
• pyproject.toml with setuptools backend
• Pre-generated C file for installation without Cython
• GitHub Actions CI: 3 OSes × 5 Python versions + pure-Python job

Breaking Changes

• Python 2 dropped
• adjustSizes=True now raises NotImplementedError (was silently ignored)
• multiThreaded=True now raises NotImplementedError (was silently ignored)
• Invalid parameter values (negative scalingRatio, etc.) now raise ValueError

Issues Closed

#25 #29 #30 #34 #39 #41 #43

PRs Incorporated

#24 #42 #47 #49 #50 #46 #37

PyPI: https://pypi.org/project/fa2/0.9.0/

pip install fa2==0.9.0