Javascript calculate the toFixed precision for a given range

calcRangePrecision.js

/**
 * Calculates the toFixed precision required for nicely displaying
 * step intervals between the values given.
 * 
 * @param int min Minimum value in set
 * @param int max Maximum value in set
 * 
 * @return int Number.toFixed precision
 */
function calcRangePrecision(min, max) {
  if(min > max) {
    throw "Min must be smaller or equal to max";
  }
  var range = max - min;
  var steps = 0 == range ? 0 : Math.ceil(Math.log(range)/Math.LN10);
  // Return the required precision (defaults to precision 2 for a range of 1)
  return Math.max(0, 2-steps);
}