Release PyGAD 3.9.2

[ahmedfgad]

PyGAD 3.9.2

Release Date: October 16, 2026.

1. Roulette wheel selection and stochastic universal selection no longer fail with fitness values near the float limits. In PyGAD 3.9.1, a fitness of -sys.float_info.max, which some libraries give a rejected solution, made the shifted values overflow, and parent selection raised IndexError. The values are now scaled before they are shifted or added. -inf and NaN get no chance, solutions with +inf fitness share every chance equally, and a population with no finite fitness raises a clear ValueError. Ordinary non-negative fitness keeps exactly the same probabilities.
2. Regression tests cover the most negative float, huge values of both signs, huge positive values, infinite and missing values, and full runs with both selectors. The pygad.utils submodule version is 1.5.12.

[github-actions]

📊 Change summary

6 files changed · +202 / −13 lines

pie showData
    title Lines changed per file (215 total)
    "tests/test_probability_selection_extreme_fitness.py" : 110
    "pygad/utils/parent_selection.py" : 90
    "docs/source/releases.md" : 7
    "docs/source/utils.md" : 4
    "pygad/_version.py" : 2
    "pygad/utils/__init__.py" : 2

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Per-file breakdown

File	+	−	total
tests/test_probability_selection_extreme_fitness.py	110	0	110
pygad/utils/parent_selection.py	81	9	90
docs/source/releases.md	7	0	7
docs/source/utils.md	2	2	4
pygad/_version.py	1	1	2
pygad/utils/__init__.py	1	1	2
Total (6 files)	202	13	215