Why can't futures be sorted by the index of Tongda letter?
There are two main reasons for sorting without data: 1. Stock software data is not downloaded; 2. The logic of ranking indicators is unreasonable, and there are few output items or output bases; 3. The sorting index is limited by the period, and the period is not selected when sorting; 4. The sorting index has a time limit, and the service period of the index has expired. A situation of 1 was encountered. ...