feat: add implementation of stats/base/dists/anglit/cdf

[bhargava-d16]

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Progresses: #9960

Description

What is the purpose of this pull request?

This pull request:

• Adds complete implementation of stats/base/dists/anglit/cdf

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Add anglit distribution implementation #9960

Questions

Any questions for reviewers of this pull request?

No.

Other

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No.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines.

AI Assistance

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• Test/benchmark generation
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[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/dists/anglit/cdf	$\color{green}323/323$ $\color{green}+100.00%$	$\color{green}27/27$ $\color{green}+100.00%$	$\color{green}4/4$ $\color{green}+100.00%$	$\color{green}323/323$ $\color{green}+100.00%$

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

[Neerajpathak07]

@bhargava-d16 Didn't get a chance to take an in-depth look. For now have left out a few comments!!

[Neerajpathak07]

Suggested change

	double y;
	static double benchmark( void ) {
	double sigma[ 100 ];
	double mu[ 100 ];
	double x[ 100 ];
	double elapsed;
	double y;

Ordering by length

[Neerajpathak07]

here this can optimized by utilizing the in-house utility of isAlmostSameValue from @stdlib/assert/is-almost-same-value.
Ref:-

stdlib/lib/node_modules/@stdlib/stats/base/dists/wald/pdf/test/test.pdf.js

Line 214 in 8336cd9

t.ok( isAlmostSameValue( y, expected[i], 1500 ), 'within tolerance. x: '+x[ i ]+'. mu: '+mu[i]+'. lambda: '+lambda[i]+'. y: '+y+'. E: '+expected[ i ]+'.' );

If you feel this adds more value do go ahead and update it in the other test files as well.

[Neerajpathak07]

Let's sync this description documented here with the one used for the C implementation at main.c.

[Planeshifter]

Missing article "an" before "anglit". Should be "for an anglit distribution" here and "of an anglit distribution" on line 47.

Suggested change

	Evaluates the cumulative distribution function (CDF) for anglit
	Evaluates the cumulative distribution function (CDF) for an anglit

[Planeshifter]

Same missing article here:

Suggested change

	function (CDF) of anglit distribution with location parameter
	function (CDF) of an anglit distribution with location parameter

[Planeshifter]

Missing article "an" before "Anglit" in several places in this file. Let's also be consistent and use lowercases here.

Suggested change

	* Evaluates the cumulative distribution function (CDF) for Anglit distribution.
	* Evaluates the cumulative distribution function (CDF) for an anglit distribution.

[Planeshifter]

Two things: sigma should be typed {PositiveNumber} (since sigma <= 0 returns NaN), and the return type should be {Probability}, not {number}.

Suggested change

	* @param {number} mu - location parameter
	* @param {number} sigma - scale parameter
	* @returns {number} evaluated CDF
	*
	* @param {number} x - input value
	* @param {number} mu - location parameter
	* @param {PositiveNumber} sigma - scale parameter
	* @returns {Probability} evaluated CDF

[Planeshifter]

Return type should be {Probability}.

Suggested change

	* @returns {number} evaluated CDF
	* @returns {Probability} evaluated CDF

[Planeshifter]

Same as main.js: sigma should be {PositiveNumber} and return type should be {Probability}.

Suggested change

	* @param {number} x - input value
	* @param {number} mu - location parameter
	* @param {number} sigma - scale parameter
	* @returns {number} evaluated CDF
	* @param {number} x - input value
	* @param {number} mu - location parameter
	* @param {PositiveNumber} sigma - scale parameter
	* @returns {Probability} evaluated CDF

[Planeshifter]

Missing spaces inside the parentheses per stdlib style:

Suggested change

	y = cdf(x[ i % x.length ], mu[ i % mu.length ], sigma[ i % sigma.length ]);
	y = cdf( x[ i % x.length ], mu[ i % mu.length ], sigma[ i % sigma.length ] );