npm package: @stdlib/number-float64-base
Description: Base utilities for double-precision floating-point numbers.
Author: The Stdlib Authors
Latest version: 0.3.1

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<details>
  <summary>
    About stdlib...
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</details>

# Float64

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

> Base utilities for double-precision floating-point numbers.

<section class="installation">

## Installation

```bash
npm install @stdlib/number-float64-base
```

</section>

<section class="usage">

## Usage

```javascript
var ns = require( '@stdlib/number-float64-base' );
```

#### ns

Base utilities for double-precision floating-point numbers.

```javascript
var o = ns;
// returns {...}
```

<!-- <toc pattern="*"> -->

<div class="namespace-toc">

-   <span class="signature">[`add( x, y )`][@stdlib/number/float64/base/add]</span><span class="delimiter">: </span><span class="description">compute the sum of two double-precision floating-point numbers.</span>
-   <span class="signature">[`add3( x, y, z )`][@stdlib/number/float64/base/add3]</span><span class="delimiter">: </span><span class="description">compute the sum of three double-precision floating-point numbers.</span>
-   <span class="signature">[`add4( x, y, z, w )`][@stdlib/number/float64/base/add4]</span><span class="delimiter">: </span><span class="description">compute the sum of four double-precision floating-point numbers.</span>
-   <span class="signature">[`add5( x, y, z, w, u )`][@stdlib/number/float64/base/add5]</span><span class="delimiter">: </span><span class="description">compute the sum of five double-precision floating-point numbers.</span>
-   <span class="signature">[`assert`][@stdlib/number/float64/base/assert]</span><span class="delimiter">: </span><span class="description">base double-precision floating-point number assert functions.</span>
-   <span class="signature">[`div( x, y )`][@stdlib/number/float64/base/div]</span><span class="delimiter">: </span><span class="description">divide two double-precision floating-point numbers.</span>
-   <span class="signature">[`exponent( x )`][@stdlib/number/float64/base/exponent]</span><span class="delimiter">: </span><span class="description">return an integer corresponding to the unbiased exponent of a double-precision floating-point number.</span>
-   <span class="signature">[`fromBinaryString( bstr )`][@stdlib/number/float64/base/from-binary-string]</span><span class="delimiter">: </span><span class="description">create a double-precision floating-point number from a literal bit representation.</span>
-   <span class="signature">[`fromInt64Bytes( bytes, stride, offset )`][@stdlib/number/float64/base/from-int64-bytes]</span><span class="delimiter">: </span><span class="description">convert a signed 64-bit integer byte array to a double-precision floating-point number.</span>
-   <span class="signature">[`fromWords( high, low )`][@stdlib/number/float64/base/from-words]</span><span class="delimiter">: </span><span class="description">create a double-precision floating-point number from a higher order word and a lower order word.</span>
-   <span class="signature">[`getHighWord( x )`][@stdlib/number/float64/base/get-high-word]</span><span class="delimiter">: </span><span class="description">return an unsigned 32-bit integer corresponding to the more significant 32 bits of a double-precision floating-point number.</span>
-   <span class="signature">[`getLowWord( x )`][@stdlib/number/float64/base/get-low-word]</span><span class="delimiter">: </span><span class="description">return an unsigned 32-bit integer corresponding to the less significant 32 bits of a double-precision floating-point number.</span>
-   <span class="signature">[`identity( x )`][@stdlib/number/float64/base/identity]</span><span class="delimiter">: </span><span class="description">evaluate the identity function of a double-precision floating-point number.</span>
-   <span class="signature">[`mul( x, y )`][@stdlib/number/float64/base/mul]</span><span class="delimiter">: </span><span class="description">multiply two double-precision floating-point numbers.</span>
-   <span class="signature">[`normalize( x )`][@stdlib/number/float64/base/normalize]</span><span class="delimiter">: </span><span class="description">return a normal number `y` and exponent `exp` satisfying `x = y * 2^exp`.</span>
-   <span class="signature">[`setHighWord( x, high )`][@stdlib/number/float64/base/set-high-word]</span><span class="delimiter">: </span><span class="description">set the more significant 32 bits of a double-precision floating-point number.</span>
-   <span class="signature">[`setLowWord( x, low )`][@stdlib/number/float64/base/set-low-word]</span><span class="delimiter">: </span><span class="description">set the less significant 32 bits of a double-precision floating-point number.</span>
-   <span class="signature">[`signbit( x )`][@stdlib/number/float64/base/signbit]</span><span class="delimiter">: </span><span class="description">return a boolean indicating if the sign bit for a double-precision floating-point number is on (true) or off (false).</span>
-   <span class="signature">[`sub( x, y )`][@stdlib/number/float64/base/sub]</span><span class="delimiter">: </span><span class="description">subtract two double-precision floating-point numbers.</span>
-   <span class="signature">[`toBinaryString( x )`][@stdlib/number/float64/base/to-binary-string]</span><span class="delimiter">: </span><span class="description">return a string giving the literal bit representation of a double-precision floating-point number.</span>
-   <span class="signature">[`float64ToFloat32( x )`][@stdlib/number/float64/base/to-float32]</span><span class="delimiter">: </span><span class="description">convert a double-precision floating-point number to the nearest single-precision floating-point number.</span>
-   <span class="signature">[`float64ToInt32( x )`][@stdlib/number/float64/base/to-int32]</span><span class="delimiter">: </span><span class="description">convert a double-precision floating-point number to a signed 32-bit integer.</span>
-   <span class="signature">[`float64ToInt64Bytes( x )`][@stdlib/number/float64/base/to-int64-bytes]</span><span class="delimiter">: </span><span class="description">convert an integer-valued double-precision floating-point number to a signed 64-bit integer byte array according to host byte order (endianness).</span>
-   <span class="signature">[`float64ToUint32( x )`][@stdlib/number/float64/base/to-uint32]</span><span class="delimiter">: </span><span class="description">convert a double-precision floating-point number to an unsigned 32-bit integer.</span>
-   <span class="signature">[`toWords( x )`][@stdlib/number/float64/base/to-words]</span><span class="delimiter">: </span><span class="description">split a double-precision floating-point number into a higher order word and a lower order word.</span>
-   <span class="signature">[`ulpdiff( x, y )`][@stdlib/number/float64/base/ulp-difference]</span><span class="delimiter">: </span><span class="description">compute the number of representable double-precision floating-point values that separate two double-precision floating-point numbers along the real number line.</span>

</div>

<!-- </toc> -->

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- TODO: better examples -->

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

```javascript
var objectKeys = require( '@stdlib/utils-keys' );
var ns = require( '@stdlib/number-float64-base' );

console.log( objectKeys( ns ) );
```

</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].

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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