test: migrate stats/base/dists/rayleigh/median to ULP-based assertions

[kgryte]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates the unit tests for stats/base/dists/rayleigh/median from relative tolerance assertions to ULP difference assertions, as proposed in [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.
• replaces the delta/tol computation and corresponding t.ok( delta <= tol, ... ) assertion in test/test.native.js with t.strictEqual( isAlmostSameValue( y, expected[ i ], 0 ), true, 'returns expected value' );.
• replaces the equivalent fixture-loop assertion in test/test.js with the same ULP-based assertion, so that both test files share a single accuracy budget.
• adds a @stdlib/assert/is-almost-same-value require and removes the now unused @stdlib/math/base/special/abs and @stdlib/constants/float64/eps requires from test/test.native.js.

Only test/test.js and test/test.native.js are modified; no implementation, documentation, benchmark, or fixture files are touched. The existing NaN and invalid-parameter assertions are left as-is, as exact comparisons remain correct for those cases.

The ULP bound below is the measured minimum: 0 is both the floor of the ULP scale and the measured maximum ULP difference over the fixture set, i.e. every fixture value is reproduced exactly, so no nonzero budget is required.

Test file	Previous tolerance	ULP bound (measured minimum)
test/test.js	exact (t.strictEqual)	0
test/test.native.js	1.0 * EPS	0

Measured by computing number/float64/base/ulp-difference against test/fixtures/julia/data.json for every assertion: all 50 fixture values match exactly (ULP difference 0) for both the JavaScript and C implementations.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352

Questions

Any questions for reviewers of this pull request?

No.

Other

Any other information relevant to this pull request? This may include screenshots, references, and/or implementation notes.

• make test TESTS_FILTER=".*/stats/base/dists/rayleigh/median/.*" passes (55/55).
• The native add-on was compiled locally (node-gyp rebuild) so that test/test.native.js was actually exercised rather than skipped; it passes (55/55) against the compiled C implementation.
• Both suites were run twice at the final ULP value to confirm the results are deterministic (no FMA/architecture-dependent variation).
• make lint-javascript-tests TESTS_FILTER=".*/stats/base/dists/rayleigh/median/.*" is clean.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines.

AI Assistance

When authoring the changes proposed in this PR, did you use any kind of 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

If you answered "yes" to using AI assistance, please provide a short disclosure indicating how you used AI assistance. This helps reviewers determine how much scrutiny to apply when reviewing your contribution. Example disclosures: "This PR was written primarily by Claude Code." or "I consulted ChatGPT to understand the codebase, but the proposed changes were fully authored manually by myself.".

This PR was written by Claude Code, mirroring the migration idiom established by previously merged conversions in this family (e.g., stats/base/dists/lognormal/median, stats/base/dists/gumbel/median, stats/base/dists/normal/median). The ULP bound was measured empirically rather than guessed.

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@stdlib-js/reviewers

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Generated by Claude Code

[stdlib-bot]

Hello! 👋

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[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/dists/rayleigh/median	$\\color{green}166/166$ $\\color{green}+100.00\\%$	$\\color{green}8/8$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}166/166$ $\\color{green}+100.00\\%$

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