npm package: @stdlib/stats-incr-nanmeanabs
Description: Compute an arithmetic mean of absolute values incrementally, ignoring NaN values.
Author: The Stdlib Authors
Latest version: 0.1.1

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<details>
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# incrnanmeanabs

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

> Compute an [arithmetic mean][arithmetic-mean] of absolute values incrementally, ignoring `NaN` values.

<section class="intro">

The [arithmetic mean][arithmetic-mean] of absolute values is defined as

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

<div class="equation" align="center" data-raw-text="\mu = \frac{1}{n} \sum_{i=0}^{n-1} |x_i|" data-equation="eq:arithmetic_mean_absolute_values">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@49d8cabda84033d55d7b8069f19ee3dd8b8d1496/lib/node_modules/@stdlib/stats/incr/nanmeanabs/docs/img/equation_arithmetic_mean_absolute_values.svg" alt="Equation for the arithmetic mean of absolute values.">
    <br>
</div>

<!-- </equation> -->

</section>

<!-- /.intro -->

<section class="installation">

## Installation

```bash
npm install @stdlib/stats-incr-nanmeanabs
```

</section>

<section class="usage">

## Usage

```javascript
var incrnanmeanabs = require( '@stdlib/stats-incr-nanmeanabs' );
```

#### incrnanmeanabs()

Returns an accumulator function which incrementally computes an [arithmetic mean][arithmetic-mean] of absolute values, ignoring `NaN` values.

```javascript
var accumulator = incrnanmeanabs();
```

#### accumulator( \[x] )

If provided an input value `x`, the accumulator function returns an updated mean. If not provided an input value `x`, the accumulator function returns the current mean.

```javascript
var accumulator = incrnanmeanabs();

var mu = accumulator( 2.0 );
// returns 2.0

mu = accumulator( NaN );
// returns 2.0

mu = accumulator( -1.0 );
// returns 1.5

mu = accumulator( -3.0 );
// returns 2.0

mu = accumulator();
// returns 2.0
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   Input values are **not** type checked. If non-numeric inputs are possible, you are advised to type check and handle accordingly **before** passing the value to the accumulator function.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var uniform = require( '@stdlib/random-base-uniform' );
var bernoulli = require( '@stdlib/random-base-bernoulli' );
var incrnanmeanabs = require( '@stdlib/stats-incr-nanmeanabs' );

// Initialize an accumulator:
var accumulator = incrnanmeanabs();

// For each simulated datum, update the mean...
var i;
for ( i = 0; i < 100; i++ ) {
    accumulator( ( bernoulli( 0.8 ) < 1 ) ? NaN : uniform( -100.0, 100.0 ) );
}
console.log( accumulator() );
```

</section>

<!-- /.examples -->

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

<section class="related">

</section>

<!-- /.related -->

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

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[umd]: https://github.com/umdjs/umd
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/stats-incr-nanmeanabs/main/LICENSE

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

</section>

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