feat: add ndarray/find-last

[headlessNode]

Resolves stdlib-js/metr-issue-tracker#122.

Description

What is the purpose of this pull request?

This pull request:

• add ndarray/find-last

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• Resolves [RFC]: add ndarray/find-last metr-issue-tracker#122
• Progresses [RFC]: achieve ndarray API parity with built-in JavaScript arrays  #2656

Questions

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No.

Other

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No.

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• Read, understood, and followed the contributing guidelines.

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@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
ndarray/find-last	$\color{green}417/417$ $\color{green}+0.00%$	$\color{green}44/44$ $\color{green}+0.00%$	$\color{green}5/5$ $\color{green}+0.00%$	$\color{green}417/417$ $\color{green}+0.00%$

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

[kgryte]

/stdlib merge

[kgryte]

@headlessNode Remind me. Why is the option named sentinelValue rather than just sentinel?

[headlessNode]

@kgryte no specific reason for it being sentinelValue rather than sentinel.

[kgryte]

2c: we should rename sentinelValue to sentinel here and in ndarray/find.

[headlessNode]

@kgryte Ready for review. The CI error is due to renaming sentinelValue. I'll open a PR to change that for ndarray/find. Need to merge #9307 first.

[kgryte]

LGTM after extensive clean-up. There were a number of things wrong with this PR. Two notable things which perhaps could have been caught given some reflection:

1. All results were transposed. This should have been an obvious sign that things were not implemented correctly. You failed to account for the fact that, if find were provided a reversed input ndarray view, it would also write values in the opposite order as well. Hence, you needed to flip the output array, in addition to the input array.
2. For similar reasons to (1), the indices being passed to the callback were not correct. Those indices were from the perspective of the view, not the original array. Hence, you needed to compute the complement of the indices in the callback wrapper.

[kgryte]

For METR,

review_time: 120 minutes