div2.js (1505B)
1 /** 2 * @license Apache-2.0 3 * 4 * Copyright (c) 2018 The Stdlib Authors. 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 'use strict'; 20 21 // MODULES // 22 23 var floor = require( '@stdlib/math/base/special/floor' ); 24 25 26 // MAIN // 27 28 /** 29 * Converts a nonnegative integer to a literal bit representation using the divide-by-2 algorithm. 30 * 31 * @private 32 * @param {NonNegativeInteger} x - nonnegative integer 33 * @returns {BinaryString} bit representation 34 * 35 * @example 36 * var v = div2( 3 ); 37 * // returns '11' 38 * 39 * @example 40 * var v = div2( 0 ); 41 * // returns '' 42 * 43 * @example 44 * var v = div2( 12 ); 45 * // returns '1100' 46 * 47 * @example 48 * var v = div2( 188 ); 49 * // returns '10111100' 50 */ 51 function div2( x ) { 52 var str = ''; 53 var y; 54 55 // We repeatedly divide by 2 and check for a remainder. If a remainder exists, the number is odd and we add a '1' bit... 56 while ( x > 0 ) { 57 y = x / 2.0; 58 x = floor( y ); 59 if ( y === x ) { 60 str = '0' + str; 61 } else { 62 str = '1' + str; 63 } 64 } 65 return str; 66 } 67 68 69 // EXPORTS // 70 71 module.exports = div2;