2 var numberIsNan = require('number-is-nan');
4 module.exports = function (num) {
5 if (typeof num !== 'number' || numberIsNan(num)) {
6 throw new TypeError('Expected a number, got ' + typeof num);
12 var units = ['B', 'kB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
19 return (neg ? '-' : '') + num + ' B';
22 exponent = Math.min(Math.floor(Math.log(num) / Math.log(1000)), units.length - 1);
23 num = Number((num / Math.pow(1000, exponent)).toFixed(2));
24 unit = units[exponent];
26 return (neg ? '-' : '') + num + ' ' + unit;