All files main.js

100% Statements 66/66
100% Branches 2/2
100% Functions 1/1
100% Lines 66/66

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 672x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 10490x 10490x 10490x 10490x 10490x 10490x 10490x 10490x 10490x 10490x 2x 2x 2x 2x 2x  
/**
* @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 getHighWord = require( '@stdlib/number/float64/base/get-high-word' );
var EXP_MASK = require( '@stdlib/constants/float64/high-word-exponent-mask' );
var BIAS = require( '@stdlib/constants/float64/exponent-bias' );
 
 
// MAIN //
 
/**
* Returns an integer corresponding to the unbiased exponent of a double-precision floating-point number.
*
* @param {number} x - input value
* @returns {integer32} unbiased exponent
*
* @example
* var exp = exponent( 3.14e-307 ); // => 2**-1019 ~ 1e-307
* // returns -1019
*
* @example
* var exp = exponent( -3.14 );
* // returns 1
*
* @example
* var exp = exponent( 0.0 );
* // returns -1023
*
* @example
* var exp = exponent( NaN );
* // returns 1024
*/
function exponent( x ) {
	// Extract from the input value a higher order word (unsigned 32-bit integer) which contains the exponent:
	var high = getHighWord( x );
 
	// Apply a mask to isolate only the exponent bits and then shift off all bits which are part of the fraction:
	high = ( high & EXP_MASK ) >>> 20;
 
	// Remove the bias and return:
	return (high - BIAS)|0; // asm type annotation
}
 
 
// EXPORTS //
 
module.exports = exponent;