@Override
  public void terminate(PointCollector pointCollector) throws Exception {
    if (!s.equals("") || !method.equals("")) { // When user offers at least one parameter
      DWTUtil transformer = new DWTUtil(method, s, layer, value);
      transformer.inverse();
      double[] r = transformer.getData();
      for (int i = 0; i < r.length; i++) {
        pointCollector.putDouble(timestamp.get(i), r[i]);
      }
    }
  }
This function calculates inverse discrete wavelet transform of an input series, which is composed
of multiple layers. Input series must be an integer exponent of 2. Input series is treated as
sampled in equal distances.
library-udf/src/main/java/org/apache/iotdb/library/frequency/UDTFIDWT.java