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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.
*/
 
'use strict';
 
// MODULES //
 
var Uint32Array = require( '@stdlib/array/uint32' );
var Float64Array = require( '@stdlib/array/float64' );
var HIGH = require( './high.js' );
 
 
// VARIABLES //
 
var FLOAT64_VIEW = new Float64Array( 1 );
var UINT32_VIEW = new Uint32Array( FLOAT64_VIEW.buffer );
 
 
// MAIN //
 
/**
* Returns an unsigned 32-bit integer corresponding to the more significant 32 bits of a double-precision floating-point number.
*
* ## Notes
*
* ```text
* float64 (64 bits)
* f := fraction (significand/mantissa) (52 bits)
* e := exponent (11 bits)
* s := sign bit (1 bit)
*
* |-------- -------- -------- -------- -------- -------- -------- --------|
* |                                Float64                                |
* |-------- -------- -------- -------- -------- -------- -------- --------|
* |              Uint32               |               Uint32              |
* |-------- -------- -------- -------- -------- -------- -------- --------|
* ```
*
* If little endian (more significant bits last):
*
* ```text
*                         <-- lower      higher -->
* |   f7       f6       f5       f4       f3       f2    e2 | f1 |s|  e1  |
* ```
*
* If big endian (more significant bits first):
*
* ```text
*                         <-- higher      lower -->
* |s| e1    e2 | f1     f2       f3       f4       f5        f6      f7   |
* ```
*
* In which Uint32 can we find the higher order bits? If little endian, the second; if big endian, the first.
*
* ## References
*
* -   [Open Group][1]
*
* [1]: http://pubs.opengroup.org/onlinepubs/9629399/chap14.htm
*
* @param {number} x - input value
* @returns {uinteger32} higher order word
*
* @example
* var w = getHighWord( 3.14e201 ); // => 01101001110001001000001011000011
* // returns 1774486211
*/
function getHighWord( x ) {
	FLOAT64_VIEW[ 0 ] = x;
	return UINT32_VIEW[ HIGH ];
}
 
 
// EXPORTS //
 
module.exports = getHighWord;