npm package: @stdlib/napi-create-double
Description: Convert a double-precision floating-point number to a Node-API value.
Author: The Stdlib Authors
Latest version: 0.0.3

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<details>
  <summary>
    About stdlib...
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# create_double

[![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 double-precision floating-point number to a Node-API value.

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</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/napi-create-double
```

</section>

<section class="usage">

## Usage

```javascript
var headerDir = require( '@stdlib/napi-create-double' );
```

#### headerDir

Absolute file path for the directory containing header files for C APIs.

```javascript
var dir = headerDir;
// returns <string>
```

</section>

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</section>

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<section class="examples">

## Examples

```javascript
var headerDir = require( '@stdlib/napi-create-double' );

console.log( headerDir );
// => <string>
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

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</section>

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<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
#include "stdlib/napi/create_double.h"
```

#### stdlib_napi_create_double( env, value, \*out )

Converts a double-precision floating-point number to a Node-API value.

```c
#include "stdlib/napi/create_double.h"
#include <node_api.h>

static napi_value addon( napi_env env, napi_callback_info info ) {

    // ...

    napi_value value;
    napi_status status = stdlib_napi_create_double( env, 1.0, &value );
    assert( status == napi_ok );
    if ( err != NULL ) {
        assert( napi_throw( env, err ) == napi_ok );
        return NULL;
    }

    // ...
}
```

The function accepts the following arguments:

-   **env**: `[in] napi_env` environment under which the function is invoked.
-   **value**: `[in] double` double-precision floating-point number.
-   **out**: `[out] napi_value*` destination for storing output value.

```c
napi_status stdlib_napi_create_double( const napi_env env, const double value, napi_value *out );
```

The function returns a `napi_status` status code indicating success or failure (returns `napi_ok` if success).

#### STDLIB_NAPI_CREATE_DOUBLE( env, expression, name )

Macro for converting a double-precision floating-point number to a Node-API value.

```c
#include "stdlib/napi/create_double.h"
#include "stdlib/napi/argv_double.h"
#include "stdlib/napi/argv.h"
#include <node_api.h>

static double fcn( const double v ) {
    return v;
}

// ...

static napi_value addon( napi_env env, napi_callback_info info ) {
    // Retrieve add-on callback arguments:
    STDLIB_NAPI_ARGV( env, info, argv, argc, 1 );

    // Convert the first argument to a C type:
    STDLIB_NAPI_ARGV_DOUBLE( env, value, argv, 0 );

    // ...

    // Convert a value having a C type to a Node-API value:
    STDLIB_NAPI_CREATE_DOUBLE( env, fcn( value ), out );

    return out;
}
```

The macro expects the following arguments:

-   **env**: environment under which the callback is invoked.
-   **expression**: expression returning a double-precision floating-point number.
-   **name**: output variable name.

</section>

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

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</section>

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<section class="examples">

</section>

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</section>

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</section>

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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].

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[test-url]: https://github.com/stdlib-js/napi-create-double/actions/workflows/test.yml?query=branch:v0.0.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/napi-create-double/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/napi-create-double?branch=main

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