docs: public double computeValue(double srcValue)
      {
          double fldTimeField = 0;
          if (m_fldTimeField != null)
              fldTimeField = m_fldTimeField.getValue();
          else
              fldTimeField = 0;
          double dateThisDate = ((DateTimeField)this.getOwner()).getValue();
          double newDateTime = dateThisDate + fldTimeField * DBConstants.KMS_IN_A_DAY;  // Rounded number of days
          return newDateTime;    // Difference between this date and target
      }