Kobold

function roundToSignificantFigures(num, sigFigs, truncationFunc) {
  if (num == 0) {
      return 0;
  }

  // We use base 5 because it makes for pretty numbers without intervals
  // quite as large as base 10.
  var d = Math.ceil(Math.log(num < 0 ? -num: num) / Math.log(5));
  var power = sigFigs - d;