dataframe's index is blank,
![image](https://user-images.githubusercontent.com/17948924/63857928-26588d80-c9d7-11e9-9a4f-1454979d6723.png)

![image](https://user-images.githubusercontent.com/17948924/63857961-3a03f400-c9d7-11e9-8e41-efcd684293e1.png)


a daraframe have valida shape number, but its index is a blank list, which start from 0,end at 0. it is so weird!!!