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isNegativeInteger

$Build Status$

Test if a finite double-precision floating-point number is a negative integer.

Usage

import isNegativeInteger from 'https://cdn.jsdelivr.net/gh/stdlib-js/math-base-assert-is-negative-integer@esm/index.mjs';

isNegativeInteger( x )

Tests if a finite double-precision floating-point number is a negative integer.

var bool = isNegativeInteger( -1.0 );
// returns true

bool = isNegativeInteger( 0.0 );
// returns false

bool = isNegativeInteger( 10.0 );
// returns false

Notes

The function assumes a finite number. If provided negative infinity, the function will return true, when, in fact, the result is undefined. If x can be infinite, wrap the implementation as follows:

function check( x ) {
    return (
        x > -Infinity &&
        isNegativeInteger( x )
    );
}

var bool = check( -Infinity );
// returns false

Examples

<!DOCTYPE html>
<html lang="en">
<body>
<script type="module">

import isNegativeInteger from 'https://cdn.jsdelivr.net/gh/stdlib-js/math-base-assert-is-negative-integer@esm/index.mjs';

var bool = isNegativeInteger( -5.0 );
// returns true

bool = isNegativeInteger( 0.0 );
// returns false

bool = isNegativeInteger( 1.0 );
// returns false

bool = isNegativeInteger( -3.14 );
// returns false

bool = isNegativeInteger( NaN );
// returns false

</script>
</body>
</html>

See Also

@stdlib/math-base/assert/is-integer: test if a finite double-precision floating-point number is an integer.
@stdlib/math-base/assert/is-nonnegative-integer: test if a finite double-precision floating-point number is a nonnegative integer.
@stdlib/math-base/assert/is-nonpositive-integer: test if a finite double-precision floating-point number is a nonpositive integer.
@stdlib/math-base/assert/is-positive-integer: test if a finite double-precision floating-point number is a positive integer.

Notice

This package is part of stdlib, a standard library 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, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2025. The Stdlib Authors.

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