README.md

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

---

C APIs

Usage

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

stdlib_base_is_nonpositive_integer( x )

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

#include <stdbool.h>

bool out = stdlib_base_is_nonpositive_integer( -5.0 );
// returns true

out = stdlib_base_is_nonpositive_integer( 0.0 );
// returns true

The function accepts the following arguments:

• x: [in] double input value.

bool stdlib_base_is_nonpositive_integer( const double x );

Examples

#include "stdlib/math/base/assert/is_nonpositive_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_nonpositive_integer( x[ i ] );
        printf( "x = %lf, is_nonpositive_integer(x) = %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-negative-integer: test if a finite double-precision floating-point number is a negative 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-positive-integer: test if a finite double-precision floating-point number is a positive integer.