mathlib-fp v1.9.1

Version 1.9.1 is a feature-frozen stabilisation and documentation-delivery release for the public 1.9 API. It adds no public type, algorithm family, overload, default, or deprecation.

Correctness fix

• Seeded TStatsKit.BootstrapMean and BootstrapConfidenceInterval now use the shared explicit-state generator's unbiased bounded-index sampling. The former private LCG/modulo path reused weak low bits; for an eight-element input it selected every element exactly once per resample and could collapse a percentile interval to the sample mean. A permanent power-of-two-length regression verifies varying resamples, a non-degenerate interval, deterministic replay, and unchanged global RandSeed.

Documentation and first use

• The versioned documentation site identifies 1.9.1 as current while retaining the generated 1.9.0 site from its tagged sources.
• The release publishes a deterministic offline HTML archive and adjacent SHA-256 file. Web and offline HTML are generated by the same dependency-free builder from reviewed repository Markdown.
• Every runnable documentation program that prints a result now has an adjacent exact or ordered-substring output contract. The checker verifies numerical values and iterative statuses, not only a zero exit code.
• The dense solve, solver-selection, sparse workflow, and migration examples publish checked output/status contracts and end with checked success markers.
• The 1.9 feedback route asks specifically about installation time, confusing type choices, boilerplate conversions, unexpected errors, missing selection guidance, and migration problems.

Install

Download the tagged source as .tar.gz or .zip, extract it, and compile the README program with src/ on the unit search path. No configure step, network access, foreign binary, or third-party runtime package is required.

Compatibility and limitations

The checked public-api-1.9.json snapshot and all 2,880 owner/signature-aware declaration rows are unchanged from 1.9.0. Existing 1.9 source remains compatible. The algorithm and scale limitations listed in the 1.9 capability inventory are unchanged; 1.9.1 does not pull forward any 1.9.2 learning-path or later convergence work.

See the 1.9.1 qualification report for the exact normal, optimised, checked/heap-traced, example, documentation, package, and clean-archive gates.