The original code is written by Dr. Li Jianping in Fortran77 on May 12, 1998.

http://lijianping.cn/dct/attach/Y2xiOmNsYjpmOjk4Mw== (retrieved on May 5, 2022)

This python version is by CUI Yingzhe, May 5, 2022. Email: [email protected]