@Override
  public void validate(UDFParameterValidator validator) throws Exception {
    validator
        .validateInputSeriesNumber(2)
        .validateInputSeriesDataType(0, Type.DOUBLE, Type.FLOAT, Type.INT32, Type.INT64)
        .validateInputSeriesDataType(1, Type.DOUBLE, Type.FLOAT, Type.INT32, Type.INT64);
  }
This function calculates convolution of two input series.
library-udf/src/main/java/org/apache/iotdb/library/frequency/UDTFConv.java