"use strict";
var log = Math.log, LOG2E = Math.LOG2E;
module.exports = function (value) {
if (isNaN(value)) return NaN;
value = Number(value);
if (value < 0) return NaN;
if (value === 0) return -Infinity;
if (value === 1) return 0;
if (value === Infinity) return Infinity;
return log(value) * LOG2E;
};