* first commit
* tmp commit
* tmp commit
* tmp
* finish base module
* tmp commit
* tmp commit
* first finish
* minor refine
* clean the code
* delete design
* refine
* minor refine
* fix as comment
* fix as comment
* refine from jupyter notebook
* minor refine
* split model.md to model.md and initialize.md
* minor refine
* minor refine
* make link availiable
* fix as chengqi comment
* fix as chengqi comment
* fix link
* fix as wenwei comment
* Fix as comment
* Fix as comment
* Fix lint