isNegativeInteger

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

Installation

npm install @stdlib/math-base-assert-is-negative-integer

Usage

var isNegativeInteger = require( '@stdlib/math-base-assert-is-negative-integer' );

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

var isNegativeInteger = require( '@stdlib/math-base-assert-is-negative-integer' );

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

C APIs

Usage

#include "stdlib/math/base/assert/is_negative_integer.h"

stdlib_base_is_negative_integer( x )

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

#include <stdbool.h>

bool out = stdlib_base_is_negative_integer( -4.0 );
// returns true

out = stdlib_base_is_negative_integer( 3.0 );
// returns false

The function accepts the following arguments:

• x: [in] double input value.

bool stdlib_base_is_negative_integer( const double x );

Examples

#include "stdlib/math/base/assert/is_negative_integer.h"
#include <stdio.h>
#include <stdbool.h>

int main( void ) {
    const double x[] = { 5.0, -5.0, 3.14, -3.14, 0.0, 0.0/0.0 };

    bool b;
    int i;
    for ( i = 0; i < 6; i++ ) {
        b = stdlib_base_is_negative_integer( x[ i ] );
        printf( "Value: %lf. Is negative integer? %s.\n", x[ i ], ( b ) ? "True" : "False" );
    }
}

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 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, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.