npm package: @stdlib/number-float64-base-from-words
Description: Create a double-precision floating-point number from a higher order word and a lower order word.
Author: The Stdlib Authors
Latest version: 0.2.3

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# From Words

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

> Create a [double-precision floating-point number][ieee754] from a higher order word and a lower order word.

<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

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

#### fromWords( high, low )

Creates a [double-precision floating-point number][ieee754] from a higher order word (unsigned 32-bit `integer`) and a lower order word (unsigned 32-bit `integer`).

```javascript
var v = fromWords( 1774486211, 2479577218 );
// returns 3.14e201

v = fromWords( 3221823995, 1413754136 );
// returns -3.141592653589793

v = fromWords( 0, 0 );
// returns 0.0

v = fromWords( 2147483648, 0 );
// returns -0.0

v = fromWords( 2146959360, 0 );
// returns NaN

v = fromWords( 2146435072, 0 );
// returns Infinity

v = fromWords( 4293918720, 0 );
// returns -Infinity
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   For more information regarding higher and lower order words, see [to-words][@stdlib/number/float64/base/to-words].

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var randu = require( '@stdlib/random-base-randu' );
var round = require( '@stdlib/math-base-special-round' );
var MAX_UINT32 = require( '@stdlib/constants-uint32-max' );
var fromWords = require( '@stdlib/number-float64-base-from-words' );

var high;
var low;
var x;
var i;

for ( i = 0; i < 100; i++ ) {
    high = round( randu()*MAX_UINT32 );
    low = round( randu()*MAX_UINT32 );
    x = fromWords( high, low );
    console.log( 'higher: %d. lower: %d. float: %d.', high, low, x );
}
```

</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/float64/base/from_words.h"
```

#### stdlib_base_float64_from_words( high, low, \*x )

Creates a double-precision floating-point number from a higher order word and a lower order word.

```c
#include <stdint.h>

uint32_t high = 1074339512;
uint32_t low = 1374389535;

double x;
stdlib_base_float64_from_words( high, low, &x );
```

The function accepts the following arguments:

-   **high**: `[in] uint32_t` higher order word.
-   **low**: `[in] uint32_t` lower order word.
-   **x**: `[out] double*` destination for a double-precision floating-point number.

```c
void stdlib_base_float64_from_words( const uint32_t high, const uint32_t low, double *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/float64/base/from_words.h"
#include <stdint.h>
#include <stdio.h>

int main( void ) {
    uint32_t high = 1074339512;
    uint32_t low[] = { 0, 10000, 1000000, 1374389535 };

    double x;
    int i;
    for ( i = 0; i < 4; i++ ) {
        stdlib_base_float64_from_words( high, low[ i ], &x );
        printf( "high: %u, low: %u => %lf\n", high, low[ i ], x );
    }
}
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/number-float32/base/from-word`][@stdlib/number/float32/base/from-word]</span><span class="delimiter">: </span><span class="description">create a single-precision floating-point number from an unsigned integer corresponding to an IEEE 754 binary representation.</span>

</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].

#### Community

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---

## License

See [LICENSE][stdlib-license].


## Copyright

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

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

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

[@stdlib/number/float64/base/to-words]: https://www.npmjs.com/package/@stdlib/number-float64-base-to-words

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