@stdlib/stats/incr/nancount/README.md

Standard library statistical functions.

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# incrnancount

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

<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="links">

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

[@stdlib/stats/incr/nansum]: https://github.com/stdlib-js/stats/tree/main/incr/nansum

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</section>

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