npm package: @stdlib/stats-incr-nancount
Description: Compute a count incrementally, ignoring NaN values.
Author: The Stdlib Authors
Latest version: 0.2.3

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

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

> Compute a count incrementally, ignoring `NaN` values.

<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

```javascript
var incrnancount = require( '@stdlib/stats-incr-nancount' );
```

#### incrnancount()

Returns an accumulator `function` which incrementally computes a count, ignoring `NaN` values.

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

#### accumulator( \[x] )

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

```javascript
var accumulator = incrnancount();

var count = accumulator( 2.0 );
// returns 1

count = accumulator( 1.0 );
// returns 2

count = accumulator( NaN );
// returns 2

count = accumulator( 3.0 );
// returns 3

count = accumulator();
// returns 3
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

```javascript
var randu = require( '@stdlib/random-base-randu' );
var incrnancount = require( '@stdlib/stats-incr-nancount' );

var accumulator;
var v;
var i;

// Initialize an accumulator:
accumulator = incrnancount();

// For each simulated datum, update the count...
for ( i = 0; i < 100; i++ ) {
    if ( randu() < 0.2 ) {
        v = NaN;
    } else {
        v = randu() * 100.0;
    }
    accumulator( v );
}
console.log( accumulator() );
```

</section>

<!-- /.examples -->

<!-- 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-incr/nansum`][@stdlib/stats/incr/nansum]</span><span class="delimiter">: </span><span class="description">compute a sum incrementally, ignoring NaN values.</span>

</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>

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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-incr-nancount/tree/deno
[deno-readme]: https://github.com/stdlib-js/stats-incr-nancount/blob/deno/README.md
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[esm-url]: https://github.com/stdlib-js/stats-incr-nancount/tree/esm
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/stats-incr-nancount/main/LICENSE

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

[@stdlib/stats/incr/nansum]: https://www.npmjs.com/package/@stdlib/stats-incr-nansum

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

</section>

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