npm package: @stdlib/number-float64-base-assert-is-same-value
Description: Test if two double-precision floating-point numbers are the same value.
Author: The Stdlib Authors
Latest version: 0.2.2

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# isSameValue

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

> Test if two double-precision floating-point numbers are the same value.

<section class="installation">

## Installation

```bash
npm install @stdlib/number-float64-base-assert-is-same-value
```

</section>

<section class="usage">

## Usage

```javascript
var isSameValue = require( '@stdlib/number-float64-base-assert-is-same-value' );
```

#### isSameValue( a, b )

Tests if two double-precision floating-point numbers `a` and `b` are the same value.

```javascript
var bool = isSameValue( 3.14, 3.14 );
// returns true

bool = isSameValue( 5.0, 3.0 );
// returns false
```

In contrast to the strict equality operator `===`, the function distinguishes between `+0` and `-0` and treats `NaNs` as the same value.

<!-- eslint-disable no-compare-neg-zero, use-isnan -->

```javascript
var bool = ( 0.0 === -0.0 );
// returns true

bool = isSameValue( 0.0, -0.0 );
// returns false

bool = isSameValue( -0.0, -0.0 );
// returns true

bool = ( NaN === NaN );
// returns false

bool = isSameValue( NaN, NaN );
// returns true
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   The function implements the [SameValue Algorithm][ecma-262-same-value-algorithm] as specified in ECMAScript 5.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var isSameValue = require( '@stdlib/number-float64-base-assert-is-same-value' );

var bool = isSameValue( 3.14, 3.14 );
// returns true

bool = isSameValue( 0.0, 0.0 );
// returns true

bool = isSameValue( -0.0, 0.0 );
// returns false

bool = isSameValue( NaN, NaN );
// returns true
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

<!-- /.intro -->

<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
#include "stdlib/number/float64/base/assert/is_same_value.h"
```

#### stdlib_base_float64_is_same_value( a, b )

Tests if two double-precision floating-point numbers `a` and `b` are the same value.

```c
#include <stdbool.h>

bool v = stdlib_base_float64_is_same_value( 3.14, 3.14 );
// returns true

v = stdlib_base_float64_is_same_value( 0.0, -0.0 );
// returns false
```

The function accepts the following arguments:

-   **a**: `[in] double` first input value.
-   **b**: `[in] double` second input value.

```c
bool stdlib_base_float64_is_same_value( const double a, const double b );
```

</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/assert/is_same_value.h"
#include <stdbool.h>
#include <stdio.h>

int main( void ) {
    const double a[] = {
        5.0,
        -2.0,
        0.0,
        0.0/0.0
    };
    const double b[] = {
        5.0,
        2.0,
        -0.0,
        0.0/0.0
    };

    bool v;
    int i;
    for ( i = 0; i < 4; i++ ) {
        v = stdlib_base_float64_is_same_value( a[ i ], b[ i ] );
        printf( "Same value? %s\n", ( v ) ? "True" : "False" );
    }
}
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

<!-- 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].

#### 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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[umd]: https://github.com/umdjs/umd
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[ecma-262-same-value-algorithm]: http://ecma-international.org/ecma-262/5.1/#sec-9.12

</section>

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