I am looking for a way to make n (e.g. 20) groups in a dataframe by a specific column by percentile. (data type is float). I am not sure if the group by quantile function can take care of this, and if it can, how the code should look like.

There are 3 rows a, b, c

i.e. Data are sorted by column 'a', and make 20 groups

* Group 1 = 0 to 5 percentile
* Group 2 = 5 to 10 percentile  

.  

.  

.
* Group 20 = 95 to 100 percentile.

would there also be a way to find the mean a, b, and c of each group, and sort them into another dataframe?