feat: add C implementation for stats/base/ndarray/smeanpw

[AtharvaPatange]

Resolves none

Description

What is the purpose of this pull request?

This pull request:

• feat: add C implementation for stats/base/ndarray/smeanpw

Related Issues

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This pull request has the following related issues:

• none

Questions

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No.

Other

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Checklist

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AI Assistance

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{{TODO: add disclosure if applicable}}

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