I have such a data frame:
value date
2 09-12
5 09-12
3 09-12
0 09-16
1 09-16
0 09-16
...
There are totally 22
different value in the column date
. I would like to subset the data frame in 22
sets, do yo know how to do it? Thanks!
Clarify:
my question is marked as duplicate now. Indeed, they are different. Subset or split one date frame is easy. But how can I apply them in a list of data frames? What I want is a list of subsets, not only single one.