isNonPositiveInteger

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

Usage

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

isNonPositiveInteger( x )

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

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

bool = isNonPositiveInteger( 0.0 );
// returns true

bool = isNonPositiveInteger( 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 &&
            isNonPositiveInteger( x )
        );
    }
    
    var bool = check( -Infinity );
    // returns false
    
  • The function does not distinguish between positive and negative zero.

    var bool = isNonPositiveInteger( 0.0 );
    // returns true
    
    bool = isNonPositiveInteger( -0.0 );
    // returns true
    

Examples

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

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

bool = isNonPositiveInteger( 0.0 );
// returns true

bool = isNonPositiveInteger( 1.0 );
// returns false

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

bool = isNonPositiveInteger( NaN );
// returns false