@stdlib/math-base-special-ldexp/lib/native.js

Multiply a double-precision floating-point number by an integer power of two.

/**
* @license Apache-2.0
*
* Copyright (c) 2022 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 addon = require( './../src/addon.node' );


// MAIN //

/**
* Multiplies a double-precision floating-point number by an integer power of two.
*
* @private
* @param {number} frac - fraction
* @param {integer} exp - exponent
* @returns {number} double-precision floating-point number
*
* @example
* var x = ldexp( 0.5, 3 ); // => 0.5 * 2^3 = 0.5 * 8
* // returns 4.0
*
* @example
* var x = ldexp( 4.0, -2 ); // => 4 * 2^(-2) = 4 * (1/4)
* // returns 1.0
*
* @example
* var x = ldexp( 0.0, 20 );
* // returns 0.0
*
* @example
* var x = ldexp( -0.0, 39 );
* // returns -0.0
*
* @example
* var x = ldexp( NaN, -101 );
* // returns NaN
*
* @example
* var x = ldexp( Infinity, 11 );
* // returns Infinity
*
* @example
* var x = ldexp( -Infinity, -118 );
* // returns -Infinity
*/
function ldexp( frac, exp ) {
	return addon( frac, exp );
}


// EXPORTS //

module.exports = ldexp;