precision.js 351 B

1234567891011
  1. exports = function(num) {
  2. num = num.toExponential().match(regExponential);
  3. var coefficient = num[1];
  4. var exponent = parseInt(num[2], 10);
  5. var places = (coefficient.split('.')[1] || '').length;
  6. var ret = places - exponent;
  7. return ret < 0 ? 0 : ret;
  8. };
  9. var regExponential = /^(-?\d?\.?\d+)e([+-]\d)+/;
  10. module.exports = exports;