test: migrate stats/base/dists/betaprime/logpdf to ULP-based assertions

[kgryte]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates the tests for stats/base/dists/betaprime/logpdf from relative tolerance testing to ULP difference testing, per [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.

The computed delta/tol comparisons in the fixture loops of test/test.logpdf.js, test/test.factory.js, and test/test.native.js are replaced with isAlmostSameValue( y, expected[ i ], <ulp> ) assertions, and the now-unused @stdlib/math/base/special/abs and @stdlib/constants/float64/eps requires are dropped in favor of @stdlib/assert/is-almost-same-value. No other test cases were touched; the exact comparisons elsewhere in these files are unchanged.

The ULP bounds are the measured minimums over each full fixture set (bisected per fixture file, and confirmed by observing a failure at N-1):

Fixture	ULP bound
fixtures/julia/both_large.json	32768
fixtures/julia/large_alpha.json	384
fixtures/julia/large_beta.json	8192

The same three minimums hold for all three implementations under test (lib/main.js, lib/factory.js, and lib/native.js), so test.native.js uses the same bounds as test.logpdf.js. The suite was run twice at the final bounds, with identical results both times (3023 + 3 + 3020 + 3020 assertions passing, native addon built locally so that test.native.js was not skipped).

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 lint-javascript-tests TESTS_FILTER=".*/stats/base/dists/betaprime/logpdf/.*" is clean.
• The idiom mirrors the already-converted sibling packages stats/base/dists/betaprime/logcdf and stats/base/dists/beta/logpdf.

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, which also measured the minimum ULP bounds empirically and ran the tests and linter.

---

@stdlib-js/reviewers

🤖 Generated with Claude Code

https://claude.ai/code/session_01PoVHr24hud4A2KStzaRMPX

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Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/dists/betaprime/logpdf	$\\color{green}342/342$ $\\color{green}+100.00\\%$	$\\color{green}25/25$ $\\color{green}+100.00\\%$	$\\color{green}4/4$ $\\color{green}+100.00\\%$	$\\color{green}342/342$ $\\color{green}+100.00\\%$

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