@stdlib/math-base-assert-is-nonpositive-integer/lib/main.js

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

/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

// MODULES //

var floor = require( '@stdlib/math-base-special-floor' );


// MAIN //

/**
* Tests if a finite double-precision floating-point number is a nonpositive integer.
*
* @param {number} x - value to test
* @returns {boolean} boolean indicating whether the value is a nonpositive integer
*
* @example
* var bool = isNonPositiveInteger( -1.0 );
* // returns true
*
* @example
* var bool = isNonPositiveInteger( 0.0 );
* // returns true
*
* @example
* var bool = isNonPositiveInteger( 10.0 );
* // returns false
*/
function isNonPositiveInteger( x ) {
	return (floor(x) === x && x <= 0);
}


// EXPORTS //

module.exports = isNonPositiveInteger;