npm package: @stdlib/assert-is-almost-equal-float64array
Description: Test if two arguments are both Float64Arrays and contain respective elements which are approximately equal within a specified number of ULPs (units in the last place).
Author: The Stdlib Authors
Latest version: 0.1.1

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# isAlmostEqualFloat64Array

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

> Test if two arguments are both [Float64Arrays][@stdlib/array/float64] and contain respective elements which are [approximately equal][@stdlib/assert/is-almost-equal] within a specified number of ULPs (units in the last place).

<section class="installation">

## Installation

```bash
npm install @stdlib/assert-is-almost-equal-float64array
```

</section>

<section class="usage">

## Usage

```javascript
var isAlmostEqualFloat64Array = require( '@stdlib/assert-is-almost-equal-float64array' );
```

#### isAlmostEqualFloat64Array( v1, v2, maxULP )

Tests if two arguments are both [Float64Arrays][@stdlib/array/float64] and contain respective elements which are [approximately equal][@stdlib/assert/is-almost-equal] within a specified number of ULPs (units in the last place).

```javascript
var EPS = require( '@stdlib/constants-float64-eps' );
var Float64Array = require( '@stdlib/array-float64' );

var x = new Float64Array( [ 1.0, 2.0 ] );
var y = new Float64Array( [ 1.0+EPS, 2.0 ] );

var bool = isAlmostEqualFloat64Array( x, y, 0 );
// returns false

bool = isAlmostEqualFloat64Array( x, y, 1 );
// returns true

bool = isAlmostEqualFloat64Array( x, [ 1.0, 2.0 ], 1 );
// returns false
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   The function returns `false` if either input value is a `Float64Array` containing `NaN`.
-   The function does not distinguish between `-0` and `+0`, treating them as equal.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var Float64Array = require( '@stdlib/array-float64' );
var isAlmostEqualFloat64Array = require( '@stdlib/assert-is-almost-equal-float64array' );

var x = new Float64Array( [ 1.0, 2.0, 3.0 ] );
var y = new Float64Array( [ 1.0, 2.0, 3.0 ] );
var out = isAlmostEqualFloat64Array( x, y, 0 );
// returns true

x = new Float64Array( [ -0.0, 0.0, -0.0 ] );
y = new Float64Array( [ 0.0, -0.0, 0.0 ] );
out = isAlmostEqualFloat64Array( x, y, 1 );
// returns true

x = new Float64Array( [ NaN, NaN, NaN ] );
y = new Float64Array( [ NaN, NaN, NaN ] );
out = isAlmostEqualFloat64Array( x, y, 0 );
// returns false
```

</section>

<!-- /.examples -->

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<section class="related">

</section>

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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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[test-image]: https://github.com/stdlib-js/assert-is-almost-equal-float64array/actions/workflows/test.yml/badge.svg?branch=v0.1.1
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[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/assert-is-almost-equal-float64array/main.svg
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-is-almost-equal-float64array/main/LICENSE

[@stdlib/array/float64]: https://www.npmjs.com/package/@stdlib/array-float64

[@stdlib/assert/is-almost-equal]: https://www.npmjs.com/package/@stdlib/assert-is-almost-equal

</section>

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