Description

Populates the empty <section class="notes"> scaffold in two @stdlib/stats/incr package READMEs with the standard NaN-propagation warning used by 105 of the 108 packages in the namespace (97% conformance). No code, type, or test changes; documentation only.

Namespace summary

• Target: @stdlib/stats/incr — 108 non-autogenerated members.
• Features analyzed: file tree, package.json shape, README section list, REPL section list, test/benchmark/example filenames, JSDoc shape (@param/@returns/@throws/@example), validation prologue, error construction, dependencies, keywords.
• Features with a clear majority (≥75%): 10 package files at 100%, 18 package.json top-level keys at 100%, 8 keywords at 100%, {## Usage, ## Notes, ## Examples, ## See Also} README sections at ≥83%, JSDoc @example at 100%, @returns {Function} at 100%, format-based error construction at 100% (of the 60 packages that throw).
• Features without a clear majority (excluded): package.json#scripts keys (shape-driven), bench(...) call count (shape-driven), validate.js (only 2 packages — grubbs, mgrubbs).

stats/incr/covmat

Empty <section class="notes"> populated with the standard NaN-propagation warning. incrcovmat updates a persistent mean vector and co-moment matrix via Welford recursion; a single NaN input contaminates mu and C and poisons every subsequent covariance-matrix output. 105/108 packages (97%) in the namespace already document this caveat verbatim, including the scalar sibling stats/incr/covariance.

stats/incr/pcorrmat

Same fix. incrpcorrmat carries persistent means, co-moments, and per-variable standard deviations, and divides by sd[i]*sd[j] to produce the correlation matrix; a NaN input permanently corrupts means, co-moments, and standard deviations and thereby every later correlation. Mirrors the wording used by the scalar sibling stats/incr/pcorr. Sibling matrix variant stats/incr/pcorrdistmat already carries a Notes section (with a package-specific floating-point note), confirming the matrix subgroup does not follow a "no Notes" convention.

Related Issues

None.

Questions

No.

Other

Validation

Both candidates were filtered through three independent review agents before applying:

• Semantic review (opus): traced the Welford recursion in both lib/main.js files and verified that NaN propagation is the same behavior the standard warning describes — applies verbatim, no need for a package-specific rephrasing.
• Cross-reference (opus): confirmed no test in either package's test/ directory parses the README, and no sibling package or generator depends on the <section class="notes"> content of either file.
• Structural review (sonnet): confirmed the empty <section class="notes"> blocks are scaffold placeholders rather than a deliberate "no Notes" convention in the matrix subgroup, citing stats/incr/pcorrdistmat as a counterexample.

Deliberately excluded from this PR:

• stats/incr/count — also missing ## Notes. incrcount increments unconditionally, so NaN does not propagate; the boilerplate would be inaccurate. intentional-deviation.
• 15 nan* packages missing ## See Also — generator-owned auto-populated section; gating rule disallows touching it.
• 7 nan* packages without a validation prologue (nanmcv, nanmmape, nanmmse, nanmstdev, nanmsum, nanstdev, nanvariance) — each delegates to a non-nan sibling that performs the validation. intentional-deviation.
• grubbs vs mgrubbs validate.js wording drift — only 2 data points, no majority to anchor a fix.

Checklist

• Read, understood, and followed the contributing guidelines.

AI Assistance

• Yes
• No

If you answered "yes" above, how did you use AI assistance?

• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

Drafted by Claude Code as part of a cross-package drift detection routine: structural and semantic features were extracted from all 108 packages in @stdlib/stats/incr, the majority pattern was identified per feature, and outliers were flagged. Three independent agent reviews (two opus, one sonnet) confirmed both Notes-section additions as unintentional drift before the patches were applied verbatim from the namespace boilerplate. A maintainer should promote out of draft.

@stdlib-js/reviewers

Generated by Claude Code