[kgryte]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates the tests for stats/incr/mmeanstdev from computed relative-tolerance assertions to ULP-based assertions using @stdlib/assert/is-almost-same-value.

The package had a single computed-tolerance assertion, covering the corrected sample standard deviation returned when the accumulator is invoked without an input value:

delta = abs( actual[ 1 ] - expected[ 1 ] );
tol = EPS * expected[ 1 ];
t.strictEqual( delta < tol, true, 'expected: '+expected[ 1 ]+'. actual: '+actual+'. tol: '+tol+'. delta: '+delta+'.' );

which is now

t.strictEqual( isAlmostSameValue( actual[ 1 ], expected[ 1 ], 0 ), true, 'returns expected value' );

The @stdlib/math/base/special/abs and @stdlib/constants/float64/eps requires, along with the now-unused delta and tol declarations, were removed, as they were only used by the migrated assertion.

ULP bound

• Final ULP constant: 0

The bound was tightened empirically. Starting from a high bound and lowering it, the accumulator's returned standard deviation proved bit-identical to the expected value (sqrt( 19.0 )) for the tested fixture:

actual[1]   = 4.358898943540674
expected[1] = 4.358898943540674
exactly equal: true
minimum ULP = 0

0 is therefore the measured minimum and the tightest bound expressible. This matches the bound used by the already-migrated sibling package stats/incr/mmeanvar, whose test is structurally identical (same [ 2.0, 3.0, 10.0 ] dataset and window size).

Verification

• make test TESTS_FILTER=".*/stats/incr/mmeanstdev/.*" — 424/424 passing, run three times with identical results, confirming the bound is deterministic.
• eslint with etc/eslint/.eslintrc.tests.js — clean, zero findings.
• Only the package's test file is changed (+2 / -7).

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.

Opened as a draft for review of the migration idiom before marking ready.

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

This PR was authored by Claude Code running as an unattended scheduled task. It selected the package, mirrored the migration idiom from the already-converted stats/incr/mmeanvar, measured the minimum ULP bound empirically, and verified the tests and linting.

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@stdlib-js/reviewers

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Generated by Claude Code

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/incr/mmeanstdev	$\\color{green}327/327$ $\\color{green}+100.00\\%$	$\\color{green}38/38$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}327/327$ $\\color{green}+100.00\\%$

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