npm package: @stdlib/stats-iter-mean
Description: Compute the arithmetic mean over all iterated values.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
  </summary>
  <p>We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.</p>
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</details>

# itermean

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

> Compute the [arithmetic mean][arithmetic-mean] over all [iterated][mdn-iterator-protocol] values.

<section class="intro">

The [arithmetic mean][arithmetic-mean] is defined as

<!-- <equation class="equation" label="eq:arithmetic_mean" align="center" raw="\mu = \frac{1}{n} \sum_{i=0}^{n-1} x_i" alt="Equation for the arithmetic mean."> -->

<div class="equation" align="center" data-raw-text="\mu = \frac{1}{n} \sum_{i=0}^{n-1} x_i" data-equation="eq:arithmetic_mean">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@e7ac225deb396ee6d2b4d5fc1a2faa645582349f/lib/node_modules/@stdlib/stats/iter/mean/docs/img/equation_arithmetic_mean.svg" alt="Equation for the arithmetic mean.">
    <br>
</div>

<!-- </equation> -->

</section>

<!-- /.intro -->

<!-- Package usage documentation. -->

<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

```javascript
var itermean = require( '@stdlib/stats-iter-mean' );
```

#### itermean( iterator )

Computes the [arithmetic mean][arithmetic-mean] over all [iterated][mdn-iterator-protocol] values.

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

var arr = array2iterator( [ 1.0, 2.0, 3.0, 4.0 ] );

var m = itermean( arr );
// returns 2.5
```

</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 returned [`iterator`][mdn-iterator-protocol] returns `NaN`. 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.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

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

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

// Compute the arithmetic mean:
var m = itermean( rand );
// returns <number>

console.log( 'Mean: %d.', m );
```

</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/midrange`][@stdlib/stats/iter/midrange]</span><span class="delimiter">: </span><span class="description">compute the mid-range of all iterated values.</span>
-   <span class="package-name">[`@stdlib/stats-iter/mmean`][@stdlib/stats/iter/mmean]</span><span class="delimiter">: </span><span class="description">create an iterator which iteratively computes a moving arithmetic mean.</span>
-   <span class="package-name">[`@stdlib/stats-iter/stdev`][@stdlib/stats/iter/stdev]</span><span class="delimiter">: </span><span class="description">compute the corrected sample standard deviation over all iterated values.</span>
-   <span class="package-name">[`@stdlib/stats-iter/sum`][@stdlib/stats/iter/sum]</span><span class="delimiter">: </span><span class="description">compute the sum of all iterated values.</span>
-   <span class="package-name">[`@stdlib/stats-iter/variance`][@stdlib/stats/iter/variance]</span><span class="delimiter">: </span><span class="description">compute the unbiased sample variance over 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>

<!-- /.stdlib -->

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<section class="links">

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

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

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

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

[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors

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

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

[arithmetic-mean]: https://en.wikipedia.org/wiki/Arithmetic_mean

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

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

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

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

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

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

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

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</section>

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