refactor: use floating-point zero literals in stats/base/dists/rayleigh

[Planeshifter]

Description

This pull request normalizes the sigma scale-parameter validation guard in two @stdlib/stats/base/dists/rayleigh packages to compare the scale parameter against 0.0 (an explicit floating-point zero literal) rather than 0 (a bare integer literal). The explicit floating-point form is used by 12 of the 14 numeric-function packages in the namespace (86%) and is the sole form used elsewhere in @stdlib/stats/base/dists: variance and stdev were the only two lib/main.js parameter guards in the entire distribution namespace using a bare integer literal (~94% ecosystem conformance). The change is behavior-preserving, since 0 and 0.0 denote the same IEEE 754 value.

stats/base/dists/rayleigh/variance

variance/lib/main.js guarded the sigma scale parameter against a bare integer 0. The parameter is a float64 NonNegativeNumber, and the function body already uses floating-point literals throughout (4.0, 2.0); the bare integer was incidental. The guard now compares against 0.0.

stats/base/dists/rayleigh/stdev

stdev/lib/main.js carried the same bare-integer guard. It now compares against 0.0, consistent with sibling packages including mean, median, and kurtosis.

Related Issues

No.

Questions

No.

Other

The change touches only the JavaScript validation guard in each package; tests, examples, REPL fixtures, and TypeScript declarations are unaffected, and the native (C) implementations were not modified.

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

This PR was produced by Claude Code running an automated cross-package consistency check. The routine extracted structural and semantic features from every package in the rayleigh namespace, identified the explicit floating-point parameter-guard literal as the majority convention, flagged variance and stdev as the outliers, and applied the two-line normalization. The change was independently reviewed for behavior preservation and for the absence of any dependent tests or documentation.

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@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/dists/rayleigh/stdev	$\color{green}169/169$ $\color{green}+100.00%$	$\color{green}8/8$ $\color{green}+100.00%$	$\color{green}2/2$ $\color{green}+100.00%$	$\color{green}169/169$ $\color{green}+100.00%$
stats/base/dists/rayleigh/variance	$\color{green}162/162$ $\color{green}+100.00%$	$\color{green}8/8$ $\color{green}+100.00%$	$\color{green}2/2$ $\color{green}+100.00%$	$\color{green}162/162$ $\color{green}+100.00%$

The above coverage report was generated for the changes in this PR.