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# toFloat16 [![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] > Convert a [double-precision floating-point number][ieee754] to the nearest [half-precision floating-point number][half-precision-floating-point-format].
## Installation ```bash npm install @stdlib/number-float64-base-to-float16 ```
## Usage ```javascript var float64ToFloat16 = require( '@stdlib/number-float64-base-to-float16' ); ``` #### float64ToFloat16( x ) Converts a [double-precision floating-point number][ieee754] to the nearest [half-precision floating-point number][ieee754]. ```javascript var y = float64ToFloat16( 1.337 ); // returns 1.3369140625 ```
## Notes - This function may be used as a polyfill for the ES2025 built-in [`Math.f16round`][math-f16round].
## Examples ```javascript var uniform = require( '@stdlib/random-array-uniform' ); var logEachMap = require( '@stdlib/console-log-each-map' ); var float64ToFloat16 = require( '@stdlib/number-float64-base-to-float16' ); // Generate an array of random numbers: var x = uniform( 100, 0.0, 100.0 ); // Convert each double-precision floating-point number to the nearest half-precision floating-point number: logEachMap( 'float64: %f => float16: %f', x, float64ToFloat16 ); ```
* * *
## C APIs
### Usage ```c #include "stdlib/number/float64/base/to_float16.h" ``` #### stdlib_base_float64_to_float16( x ) Converts a [double-precision floating-point number][ieee754] to the nearest [half-precision floating-point number][half-precision-floating-point-format]. ```c #include "stdlib/number/float16/ctor.h" stdlib_float16_t x = stdlib_base_float64_to_float16( 3.14 ); ``` The function accepts the following arguments: - **x**: `[in] double` input value. ```c stdlib_float16_t stdlib_base_float64_to_float16( const double x ); ```
### Examples ```c #include "stdlib/number/float64/base/to_float16.h" #include "stdlib/number/float16/ctor.h" #include #include int main( void ) { const double x[] = { 3.14, -3.14, 0.0, 0.0/0.0 }; stdlib_float16_t v; int i; for ( i = 0; i < 4; i++ ) { v = stdlib_base_float64_to_float16( x[ i ] ); printf( "%lf => uint16: %d\n", x[ i ], stdlib_float16_to_bits( v ) ); } } ```
* * * ## 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 © 2016-2026. The Stdlib [Authors][stdlib-authors].
[npm-image]: http://img.shields.io/npm/v/@stdlib/number-float64-base-to-float16.svg [npm-url]: https://npmjs.org/package/@stdlib/number-float64-base-to-float16 [test-image]: https://github.com/stdlib-js/number-float64-base-to-float16/actions/workflows/test.yml/badge.svg?branch=v0.1.2 [test-url]: https://github.com/stdlib-js/number-float64-base-to-float16/actions/workflows/test.yml?query=branch:v0.1.2 [coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/number-float64-base-to-float16/main.svg [coverage-url]: https://codecov.io/github/stdlib-js/number-float64-base-to-float16?branch=main [chat-image]: https://img.shields.io/badge/zulip-join_chat-brightgreen.svg [chat-url]: https://stdlib.zulipchat.com [stdlib]: https://github.com/stdlib-js/stdlib [stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors [umd]: https://github.com/umdjs/umd [es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules [deno-url]: https://github.com/stdlib-js/number-float64-base-to-float16/tree/deno [deno-readme]: https://github.com/stdlib-js/number-float64-base-to-float16/blob/deno/README.md [umd-url]: https://github.com/stdlib-js/number-float64-base-to-float16/tree/umd [umd-readme]: https://github.com/stdlib-js/number-float64-base-to-float16/blob/umd/README.md [esm-url]: https://github.com/stdlib-js/number-float64-base-to-float16/tree/esm [esm-readme]: https://github.com/stdlib-js/number-float64-base-to-float16/blob/esm/README.md [branches-url]: https://github.com/stdlib-js/number-float64-base-to-float16/blob/main/branches.md [stdlib-license]: https://raw.githubusercontent.com/stdlib-js/number-float64-base-to-float16/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 [math-f16round]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/f16round