feat: add constants/float16/fourth-root-eps

[aryan7071]

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Description

What is the purpose of this pull request?

This pull request:

• add constants/float16/fourth-root-eps

Related Issues

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This pull request has the following related issues:

• [RFC]: tracking issue for missing float16 constants #9061

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No.

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Coverage Report

Package	Statements	Branches	Functions	Lines
constants/float16/fourth-root-eps	$\color{green}53/53$ $\color{green}+0.00%$	$\color{green}1/1$ $\color{green}+0.00%$	$\color{green}0/0$ $\color{green}+0.00%$	$\color{green}53/53$ $\color{green}+0.00%$

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

[Neerajpathak07]

@aryan7071 Left a few comments. Also, do double check if the return value fits the half-precision limit.

[Neerajpathak07]

Ohh turns out this package has been worked on in #9250.

[aryan7071]

Oh okay, @Neerajpathak07. In that case, I’ll close this for now. That PR is already 20 days old if it doesn’t move forward, I’d be happy to make the changes and commit them. Your call.

[aryan7071]

@Neerajpathak07 It seems that the related PR isn’t moving forward. Should I take this up?

[aryan7071]

@Neerajpathak07 Whenever you have the time, I’d really appreciate it if you could review this PR.

[Neerajpathak07]

@aryan7071 Overall looks in good shape, Just a few comments more to the finish line.

[Neerajpathak07]

Suggested change

	tape( 'the exported value equals the fourth root of half-precision floating-point epsilon', function test( t ) {
	tape( 'the exported value equals the fourth root of the difference between one and the smallest value greater than one which is representable as a stdlib_float16_t (2**-10)', function test( t ) {

[Neerajpathak07]

Suggested change

	var expected = float64ToFloat16(sqrt(sqrt(pow( 2.0, -10.0 ))));
	var expected = float64ToFloat16( sqrt( sqrt( pow( 2.0, -10.0 ) ) ) );

[Neerajpathak07]

Better to add the C header file for this given that we now have extended support for H_H macro?
cc:- @kgryte

[aryan7071]

okay understood!

[aryan7071]

@Neerajpathak07 could you please review this PR when you have time? I would appreciate your feedback. Thank you.

[Neerajpathak07]

Thanks for working on this, Just the comment on the header file rest looks good!!!

[Neerajpathak07]

Here we cannot represent half-precision values as float dtype. The reason being JS currently does not provide support for standalone half-precision numbers. Hence, we represent these in double dtype.

If you want to know how this was implemented in stdlib you can refer:-
https://github.com/stdlib-js/stdlib/blob/develop/lib/node_modules/%40stdlib/math/base/napi/unary/src/h_h.c