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/**
* @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.
*
*
* ## Notice
*
* The following copyright, license, and long comment were part of the original implementation available as part of [FreeBSD]{@link https://svnweb.freebsd.org/base/release/9.3.0/lib/msun/src/e_exp.c}. The implementation follows the original, but has been modified for JavaScript.
*
* ```text
* Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ```
*/
'use strict';
// MODULES //
var ldexp = require( './../../../../base/special/ldexp' );
var polyvalP = require( './polyval_p.js' );
// MAIN //
/**
* Computes \\(e^{r} 2^k\\) where \\(r = \mathrm{hi} - \mathrm{lo}\\) and \\(|r| \leq \ln(2)/2\\).
*
* @private
* @param {number} hi - upper bound
* @param {number} lo - lower bound
* @param {integer} k - power of 2
* @returns {number} function value
*/
function expmulti( hi, lo, k ) {
var r;
var t;
var c;
var y;
r = hi - lo;
t = r * r;
c = r - ( t*polyvalP( t ) );
y = 1.0 - ( lo - ( (r*c)/(2.0-c) ) - hi);
return ldexp( y, k );
}
// EXPORTS //
module.exports = expmulti;
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