npm package: @stdlib/stats-iter-cuprod
Description: Create an iterator which iteratively computes a cumulative product.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
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# itercuprod

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Create an [iterator][mdn-iterator-protocol] which iteratively computes a cumulative product.

<section class="intro">

The cumulative product is defined as

<!-- <equation class="equation" label="eq:cumulative_product" align="center" raw="\begin{align*} p_0 &= x_0 \\ p_1 &= x_1 \cdot p_0 \\ p_2 &= x_2 \cdot p_1 \\ p_n &= x_n \cdot p_{n-1} = x_n \cdot \prod_{i=0}^{n-1} x_i \end{align*}" alt="Equation for the cumulative product."> -->

<div class="equation" align="center" data-raw-text="\begin{align*} p_0 &amp;= x_0 \\ p_1 &amp;= x_1 \cdot p_0 \\ p_2 &amp;= x_2 \cdot p_1 \\ p_n &amp;= x_n \cdot p_{n-1} = x_n \cdot \prod_{i=0}^{n-1} x_i \end{align*}" data-equation="eq:cumulative_product">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@e70489fe2d16d2496f77b516c791cf5c0c078ae1/lib/node_modules/@stdlib/stats/iter/cuprod/docs/img/equation_cumulative_product.svg" alt="Equation for the cumulative product.">
    <br>
</div>

<!-- </equation> -->

</section>

<!-- /.intro -->

<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/stats-iter-cuprod
```

</section>

<section class="usage">

## Usage

```javascript
var itercuprod = require( '@stdlib/stats-iter-cuprod' );
```

#### itercuprod( iterator )

Returns an [iterator][mdn-iterator-protocol] which iteratively computes a cumulative product.

```javascript
var array2iterator = require( '@stdlib/array-to-iterator' );

var arr = array2iterator( [ 2.0, 1.0, 3.0, -7.0, -5.0 ] );
var it = itercuprod( arr );

var p = it.next().value;
// returns 2.0

p = it.next().value;
// returns 2.0

p = it.next().value;
// returns 6.0

p = it.next().value;
// returns -42.0

p = it.next().value;
// returns 210.0
```

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## Notes

-   If an iterated value is non-numeric (including `NaN`), the function returns `NaN` for **all** future iterations. If non-numeric iterated values are possible, you are advised to provide an [`iterator`][mdn-iterator-protocol] which type checks and handles non-numeric values accordingly.
-   For [iterators][mdn-iterator-protocol] which can generate many values or which may output large numbers, care should be taken to prevent overflow.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var runif = require( '@stdlib/random-iter-uniform' );
var itercuprod = require( '@stdlib/stats-iter-cuprod' );

// Create an iterator for generating uniformly distributed pseudorandom numbers:
var rand = runif( -10.0, 10.0, {
    'seed': 1234,
    'iter': 100
});

// Create an iterator for iteratively computing a cumulative product:
var it = itercuprod( rand );

// Perform manual iteration...
var v;
while ( true ) {
    v = it.next();
    if ( typeof v.value === 'number' ) {
        console.log( 'prod: %d', v.value );
    }
    if ( v.done ) {
        break;
    }
}
```

</section>

<!-- /.examples -->

<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="references">

</section>

<!-- /.references -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/stats-iter/cusum`][@stdlib/stats/iter/cusum]</span><span class="delimiter">: </span><span class="description">create an iterator which iteratively computes a cumulative sum.</span>
-   <span class="package-name">[`@stdlib/stats-iter/prod`][@stdlib/stats/iter/prod]</span><span class="delimiter">: </span><span class="description">compute the product of all iterated values.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->


<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

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[npm-image]: http://img.shields.io/npm/v/@stdlib/stats-iter-cuprod.svg
[npm-url]: https://npmjs.org/package/@stdlib/stats-iter-cuprod

[test-image]: https://github.com/stdlib-js/stats-iter-cuprod/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/stats-iter-cuprod/actions/workflows/test.yml?query=branch:v0.2.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/stats-iter-cuprod/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/stats-iter-cuprod?branch=main

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[stdlib]: https://github.com/stdlib-js/stdlib

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[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules

[deno-url]: https://github.com/stdlib-js/stats-iter-cuprod/tree/deno
[deno-readme]: https://github.com/stdlib-js/stats-iter-cuprod/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/stats-iter-cuprod/tree/umd
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[branches-url]: https://github.com/stdlib-js/stats-iter-cuprod/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/stats-iter-cuprod/main/LICENSE

[mdn-iterator-protocol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols#The_iterator_protocol

<!-- <related-links> -->

[@stdlib/stats/iter/cusum]: https://www.npmjs.com/package/@stdlib/stats-iter-cusum

[@stdlib/stats/iter/prod]: https://www.npmjs.com/package/@stdlib/stats-iter-prod

<!-- </related-links> -->

</section>

<!-- /.links -->