[AtharvaPatange]

Resolves a part of #14404

Description

What is the purpose of this pull request?

This pull request:

• Implements the ndarray API wrapper for @stdlib/blas/ext/base/dapxsumkbn (adds a scalar constant to each element in a one-dimensional double-precision floating-point ndarray and computes the sum using an improved Kahan–Babuška algorithm).
• Ensures consistency with canonical conventions across existing @stdlib/blas/ext/base/ndarray packages (such as dsumkbn and dapx).
• Includes comprehensive unit tests, benchmarks, TypeScript typings (index.d.ts and test.ts), REPL documentation, and examples.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: add ndarray interface variants for missing modules in @stdlib/blas/ext/base #14404

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.

No.

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.".

I used an AI assistant to audit remaining implementations for #14404, research reference patterns from existing ndarray packages (dapx and dsumkbn), and help scaffold tests (including KBN catastrophic cancellation and zero-sign preservation tests), benchmarks, and TypeScript definitions. All changes were manually verified and tested against the @stdlib/blas/ext/base/dapxsumkbn base implementation.

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@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
blas/ext/base/ndarray/dapxsumkbn	$\\color{green}119/119$ $\\color{green}+0.00\\%$	$\\color{green}3/3$ $\\color{green}+0.00\\%$	$\\color{green}1/1$ $\\color{green}+0.00\\%$	$\\color{green}119/119$ $\\color{green}+0.00\\%$

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