npm package: @stdlib/number-float16-base-to-float64
Description: Convert a half-precision floating-point number to the nearest double-precision floating-point number.
Author: The Stdlib Authors
Latest version: 0.1.2

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<details>
  <summary>
    About stdlib...
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  <p>We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.</p>
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# toFloat64

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

> Convert a [half-precision floating-point number][half-precision-floating-point-format] to the nearest [double-precision floating-point number][ieee754].

<section class="installation">

## Installation

```bash
npm install @stdlib/number-float16-base-to-float64
```

</section>

<section class="usage">

## Usage

```javascript
var float16ToFloat64 = require( '@stdlib/number-float16-base-to-float64' );
```

#### float16ToFloat64( x )

Converts a [half-precision floating-point number][half-precision-floating-point-format] to the nearest [double-precision floating-point number][ieee754].

```javascript
var float64ToFloat16 = require( '@stdlib/number-float64-base-to-float16' );

var y = float16ToFloat64( float64ToFloat16( 1.337 ) );
// returns 1.3369140625
```

</section>

<!-- /.usage -->

<section class="notes">

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var float64ToFloat16 = require( '@stdlib/number-float64-base-to-float16' );
var uniform = require( '@stdlib/random-array-uniform' );
var map = require( '@stdlib/array-base-map' );
var naryFunction = require( '@stdlib/utils-nary-function' );
var pickArguments = require( '@stdlib/utils-pick-arguments' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var float16ToFloat64 = require( '@stdlib/number-float16-base-to-float64' );

// Generate an array of random numbers:
var f64 = uniform( 100, 0.0, 100.0 );

// Convert each value to a half-precision floating-point number:
var f16 = map( f64, naryFunction( float64ToFloat16, 1 ) );

// Convert each half-precision floating-point number to the nearest double-precision floating-point number:
logEachMap( 'float64: %f => float16: %f => float64: %f', f64, f16, pickArguments( float16ToFloat64, [ 1 ] ) );
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

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<section class="intro">

</section>

<!-- /.intro -->

<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
#include "stdlib/number/float16/base/to_float64.h"
```

#### stdlib_base_float16_to_float64( x )

Converts a [half-precision floating-point number][half-precision-floating-point-format] to the nearest [double-precision floating-point number][ieee754].

```c
#include "stdlib/number/float16/ctor.h"

stdlib_float16_t v = stdlib_float16_from_bits( 51648 ); // => -11.5
double x = stdlib_base_float16_to_float64( v );
```

The function accepts the following arguments:

-   **x**: `[in] stdlib_float16_t` half-precision floating-point number.

```c
double stdlib_base_float16_to_float64( const stdlib_float16_t x );
```

</section>

<!-- /.usage -->

<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

</section>

<!-- /.notes -->

<!-- C API usage examples. -->

<section class="examples">

### Examples

```c
#include "stdlib/number/float16/base/to_float64.h"
#include "stdlib/number/float16/ctor.h"
#include <stdint.h>
#include <stdio.h>

int main( void ) {
    const stdlib_float16_t x[] = {
        stdlib_float16_from_bits( 51648 ), // -11.5
        stdlib_float16_from_bits( 18880 )  // 11.5
    };

    double v;
    int i;
    for ( i = 0; i < 2; i++ ) {
        v = stdlib_base_float16_to_float64( x[ i ] );
        printf( "float16 bits: %u => float64: %lf\n", stdlib_float16_to_bits( x[ i ] ), v );
    }
}
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

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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>

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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/number-float16-base-to-float64/main/LICENSE

[ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985

[half-precision-floating-point-format]: https://en.wikipedia.org/wiki/Half-precision_floating-point_format

</section>

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