time-to-botec/squiggle/node_modules/@stdlib/stats/iter/meanabs2/README.md

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# itermeanabs2

> Compute the [arithmetic mean][arithmetic-mean] of squared absolute values for all [iterated][mdn-iterator-protocol] values.

<section class="intro">

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

<!-- <equation class="equation" label="eq:arithmetic_mean_squared_absolute_values" align="center" raw="m = \frac{1}{n} \sum_{i=0}^{n-1} x_i^2" alt="Equation for the arithmetic mean of squared absolute values."> -->

<div class="equation" align="center" data-raw-text="m = \frac{1}{n} \sum_{i=0}^{n-1} x_i^2" data-equation="eq:arithmetic_mean_squared_absolute_values">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@d6537e6e0eb08987edeffda2d81b9a9197bdd7e0/lib/node_modules/@stdlib/stats/iter/meanabs2/docs/img/equation_arithmetic_mean_squared_absolute_values.svg" alt="Equation for the arithmetic mean of squared absolute values.">
    <br>
</div>

<!-- </equation> -->

</section>

<!-- /.intro -->

<!-- Package usage documentation. -->

<section class="usage">

## Usage

```javascript
var itermeanabs2 = require( '@stdlib/stats/iter/meanabs2' );
```

#### itermeanabs2( iterator )

Computes the [arithmetic mean][arithmetic-mean] of squared absolute values for 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 = itermeanabs2( arr );
// returns 7.5
```

</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 itermeanabs2 = require( '@stdlib/stats/iter/meanabs2' );

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

// Compute the arithmetic mean of squared absolute values:
var m = itermeanabs2( rand );
// returns <number>

console.log( 'meanabs2: %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 all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

[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

</section>

<!-- /.links -->