generator-website-starter
Version:
A website generator using semantic markup, SASS, Gulp, Imagemin and Browser-sync
15 lines (12 loc) • 337 B
JavaScript
;
var log = Math.log;
module.exports = function (value) {
if (isNaN(value)) return NaN;
value = Number(value);
if (value < -1) return NaN;
if (value > 1) return NaN;
if (value === -1) return -Infinity;
if (value === 1) return Infinity;
if (value === 0) return value;
return 0.5 * log((1 + value) / (1 - value));
};