Test if a value is equal to negative zero.
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> Test if a value is a number equal to negative zero.
``bash`
npm install @stdlib/assert-is-negative-zero
`javascript`
var isNegativeZero = require( '@stdlib/assert-is-negative-zero' );
#### isNegativeZero( value )
Tests if a value is a number having a value equal to negative zero.
`javascript
var Number = require( '@stdlib/number-ctor' );
var bool = isNegativeZero( -0.0 );
// returns true
bool = isNegativeZero( new Number( -0.0 ) );
// returns true
bool = isNegativeZero( -3.14 );
// returns false
bool = isNegativeZero( 0.0 );
// returns false
bool = isNegativeZero( null );
// returns false
`
#### isNegativeZero.isPrimitive( value )
Tests if a value is a primitive number equal to negative zero.
`javascript
var Number = require( '@stdlib/number-ctor' );
var bool = isNegativeZero.isPrimitive( -0.0 );
// returns true
bool = isNegativeZero.isPrimitive( new Number( -0.0 ) );
// returns false
`
#### isNegativeZero.isObject( value )
Tests if a value is a Number object having a value equal to negative zero.
`javascript
var Number = require( '@stdlib/number-ctor' );
var bool = isNegativeZero.isObject( -0.0 );
// returns false
bool = isNegativeZero.isObject( new Number( -0.0 ) );
// returns true
`
`javascript
var Number = require( '@stdlib/number-ctor' );
var isNegativeZero = require( '@stdlib/assert-is-negative-zero' );
var bool = isNegativeZero( -0.0 );
// returns true
bool = isNegativeZero( new Number( -0.0 ) );
// returns true
bool = isNegativeZero( -3.14 );
// returns false
bool = isNegativeZero( 0.0 );
// returns false
bool = isNegativeZero( 5.0 );
// returns false
bool = isNegativeZero( '-0' );
// returns false
bool = isNegativeZero( null );
// returns false
`
*
- [@stdlib/assert-is-number][@stdlib/assert/is-number]: test if a value is a number.
- [@stdlib/assert-is-positive-zero][@stdlib/assert/is-positive-zero]: test if a value is equal to positive zero.
*
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].
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---
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[deno-url]: https://github.com/stdlib-js/assert-is-negative-zero/tree/deno
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[umd-url]: https://github.com/stdlib-js/assert-is-negative-zero/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-is-negative-zero/blob/umd/README.md
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