code: public char[] ts2String(double[] vals, double[] cuts) {
      char[] res = new char[vals.length];
      for (int i = 0; i < vals.length; i++) {
        res[i] = num2char(vals[i], cuts);
      }
      return res;
    }
docs: Converts the timeseries into string using given cuts intervals. Useful for not-normal
  distribution cuts.
  
  @param vals The timeseries.
  @param cuts The cut intervals.
  @return The timeseries SAX representation.