opusdev/vector-similarity-api

1/*!2 * bytes3 * Copyright(c) 2012-2014 TJ Holowaychuk4 * Copyright(c) 2015 Jed Watson5 * MIT Licensed6 */7 8'use strict';9 10/**11 * Module exports.12 * @public13 */14 15module.exports = bytes;16module.exports.format = format;17module.exports.parse = parse;18 19/**20 * Module variables.21 * @private22 */23 24var formatThousandsRegExp = /\B(?=(\d{3})+(?!\d))/g;25 26var formatDecimalsRegExp = /(?:\.0*|(\.[^0]+)0+)$/;27 28var map = {29  b:  1,30  kb: 1 << 10,31  mb: 1 << 20,32  gb: 1 << 30,33  tb: Math.pow(1024, 4),34  pb: Math.pow(1024, 5),35};36 37var parseRegExp = /^((-|\+)?(\d+(?:\.\d+)?)) *(kb|mb|gb|tb|pb)$/i;38 39/**40 * Convert the given value in bytes into a string or parse to string to an integer in bytes.41 *42 * @param {string|number} value43 * @param {{44 *  case: [string],45 *  decimalPlaces: [number]46 *  fixedDecimals: [boolean]47 *  thousandsSeparator: [string]48 *  unitSeparator: [string]49 *  }} [options] bytes options.50 *51 * @returns {string|number|null}52 */53 54function bytes(value, options) {55  if (typeof value === 'string') {56    return parse(value);57  }58 59  if (typeof value === 'number') {60    return format(value, options);61  }62 63  return null;64}65 66/**67 * Format the given value in bytes into a string.68 *69 * If the value is negative, it is kept as such. If it is a float,70 * it is rounded.71 *72 * @param {number} value73 * @param {object} [options]74 * @param {number} [options.decimalPlaces=2]75 * @param {number} [options.fixedDecimals=false]76 * @param {string} [options.thousandsSeparator=]77 * @param {string} [options.unit=]78 * @param {string} [options.unitSeparator=]79 *80 * @returns {string|null}81 * @public82 */83 84function format(value, options) {85  if (!Number.isFinite(value)) {86    return null;87  }88 89  var mag = Math.abs(value);90  var thousandsSeparator = (options && options.thousandsSeparator) || '';91  var unitSeparator = (options && options.unitSeparator) || '';92  var decimalPlaces = (options && options.decimalPlaces !== undefined) ? options.decimalPlaces : 2;93  var fixedDecimals = Boolean(options && options.fixedDecimals);94  var unit = (options && options.unit) || '';95 96  if (!unit || !map[unit.toLowerCase()]) {97    if (mag >= map.pb) {98      unit = 'PB';99    } else if (mag >= map.tb) {100      unit = 'TB';101    } else if (mag >= map.gb) {102      unit = 'GB';103    } else if (mag >= map.mb) {104      unit = 'MB';105    } else if (mag >= map.kb) {106      unit = 'KB';107    } else {108      unit = 'B';109    }110  }111 112  var val = value / map[unit.toLowerCase()];113  var str = val.toFixed(decimalPlaces);114 115  if (!fixedDecimals) {116    str = str.replace(formatDecimalsRegExp, '$1');117  }118 119  if (thousandsSeparator) {120    str = str.split('.').map(function (s, i) {121      return i === 0122        ? s.replace(formatThousandsRegExp, thousandsSeparator)123        : s124    }).join('.');125  }126 127  return str + unitSeparator + unit;128}129 130/**131 * Parse the string value into an integer in bytes.132 *133 * If no unit is given, it is assumed the value is in bytes.134 *135 * @param {number|string} val136 *137 * @returns {number|null}138 * @public139 */140 141function parse(val) {142  if (typeof val === 'number' && !isNaN(val)) {143    return val;144  }145 146  if (typeof val !== 'string') {147    return null;148  }149 150  // Test if the string passed is valid151  var results = parseRegExp.exec(val);152  var floatValue;153  var unit = 'b';154 155  if (!results) {156    // Nothing could be extracted from the given string157    floatValue = parseInt(val, 10);158    unit = 'b'159  } else {160    // Retrieve the value and the unit161    floatValue = parseFloat(results[1]);162    unit = results[4].toLowerCase();163  }164 165  if (isNaN(floatValue)) {166    return null;167  }168 169  return Math.floor(map[unit] * floatValue);170}171