feat: add ndarray/base/rotr90

[headlessNode]

---

type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes. report:

• task: lint_filenames status: passed
• task: lint_editorconfig status: passed
• task: lint_markdown status: passed
• task: lint_package_json status: passed
• task: lint_repl_help status: passed
• task: lint_javascript_src status: passed
• task: lint_javascript_cli status: na
• task: lint_javascript_examples status: passed
• task: lint_javascript_tests status: passed
• task: lint_javascript_benchmarks status: passed
• task: lint_python status: na
• task: lint_r status: na
• task: lint_c_src status: na
• task: lint_c_examples status: na
• task: lint_c_benchmarks status: na
• task: lint_c_tests_fixtures status: na
• task: lint_shell status: na
• task: lint_typescript_declarations status: passed
• task: lint_typescript_tests status: passed
• task: lint_license_headers status: passed ---

Resolves stdlib-js/metr-issue-tracker#203.

Description

What is the purpose of this pull request?

This pull request:

• add ndarray/base/rot90

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• Resolves [RFC]: add ndarray/base/rot90 metr-issue-tracker#203

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.".

Primarily written by Claude Code.

---

@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
ndarray/base/rotr90	$\color{green}153/153$ $\color{green}+0.00%$	$\color{green}13/13$ $\color{green}+0.00%$	$\color{green}1/1$ $\color{green}+0.00%$	$\color{green}153/153$ $\color{green}+0.00%$

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

[kgryte]

@headlessNode This doesn't actually test anything other than the the input array is returned. You need to actually test against (1) the underlying data buffer, (2) the shape, (3) the strides, (4) the order.

[kgryte]

As commented in the implementation, I am not sure we should be returning the input ndarray here, but instead should be returning a view regardless.

[kgryte]

Same comment as above.

[kgryte]

@headlessNode Hmmm...what do we do elsewhere in a similar situation? Should we always be returning a view? Seems a bit odd that, here, we return the input ndarray, but when k%4 == 0, we always return a view.

I feel like we've had to do something like this before where we always return a new view regardless, especially as not doing so here effectively makes the writable parameter irrelevant under certain scenarios.

[kgryte]

Right. Just checked. In ndarray/base/fliplr, we always return a new view. We should likely follow suit here.

You'll always need to update related notes in the various docs saying that, for ndarrays having fewer than two dimensions, the function returns a new view of the input ndarray.

[kgryte]

Suggested change

	tape( 'the function supports the `writable` parameter', function test( t ) {
	tape( 'the function supports a `writable` parameter', function test( t ) {

[kgryte]

Left another round of comments. This PR is getting close.

[kgryte]

For METR,

review_time: 26 mins